nellcor npb-195 - service manual

Caution: Federal law (U.S.) restricts this device to sale by or on the order of a physician.To contact Mallinckrodt's representative: In the United States, call 1-800-635-5267 or 314-654-2000; outside the United States,call your local Mallinckrodt representative.

© 2000 Mallinckrodt Inc. All rights reserved. 035154D-0100

SERVICE MANUAL

NPB-195 Pulse Oximeter

Mallinckrodt Inc.675 McDonnell BoulevardP.O. Box 5840St. Louis, MO 63134 USATel 314.654.2000Toll Free 1.800.635.5267

MallinckrodtEurope BVHambakenwetering 15231 DD's-HertogenboschThe NetherlandsTel +31.73.6485200

Nellcor Puritan Bennett Inc.4280 Hacienda DrivePleasanton, CA 94588 USA

Nellcor Puritan Bennett Inc. is a wholly owned subsidiary of Mallinckrodt Inc. Nellcor,Nellcor Puritan Bennett, Durasensor, and Oxisensor II are trademarks of Mallinckrodt Inc.

To obtain information about a warranty, if any, for this product, contact Mallinckrodt'sTechnical Services or your local Mallinckrodt representative.

Purchase of this instrument confers no express or implied license under any Mallinckrodtpatent to use the instrument with any sensor that is not manufactured or licensed byMallinckrodt.

Covered by one or more of the following U.S. Patents and foreign equivalents: 4,621,643;4,653,498; 4,700,708; 4,770,179; 4,869,254; 5,078,136; 5,351,685; and 5,368,026.

iii

TABLE OF CONTENTSList of FiguresList of Tables

Table of Contents ........................................................................................ iiiList of Figures........................................................................................... vList of Tables ............................................................................................ vi

Section 1: Introduction .............................................................................. 1-11.1 Manual Overview.......................................................................... 1-11.2 NPB-195 Pulse Oximeter Description.......................................... 1-11.3 Power-On Self Test...................................................................... 1-41.4 Related Documents...................................................................... 1-4

Section 2: Routine Maintenance............................................................... 2-12.1 Cleaning ....................................................................................... 2-12.2 Periodic Safety and Functional Checks ....................................... 2-12.3 Battery.......................................................................................... 2-1

Section 3: Performance Verification......................................................... 3-13.1 Introduction .................................................................................. 3-13.2 Equipment Needed ...................................................................... 3-13.3 Performance Tests....................................................................... 3-13.4 Safety Tests ................................................................................. 3-9

Section 4: Power-On Settings and Service Functions ........................... 4-14.1 Introduction .................................................................................. 4-14.2 Power-On Settings ....................................................................... 4-14.3 Service Functions......................................................................... 4-2

Section 5: Troubleshooting....................................................................... 5-15.1 Introduction .................................................................................. 5-15.2 How to Use this Section ............................................................... 5-15.3 Who Should Perform Repairs ...................................................... 5-15.4 Replacement Level Supported..................................................... 5-15.5 Obtaining Replacement Parts ...................................................... 5-15.6 Troubleshooting Guide................................................................. 5-25.7 Error Codes.................................................................................. 5-7

Section 6: Disassembly Guide .................................................................. 6-16.1 Introduction .................................................................................. 6-16.2 Prior to Disassembly .................................................................... 6-16.3 Fuse Replacement ....................................................................... 6-26.4 Monitor Disassembly.................................................................... 6-36.5 Monitor Reassembly .................................................................... 6-46.6 Battery Replacement.................................................................... 6-56.7 Power Entry Module (PEM) Removal/Installation ........................ 6-76.8 Power Supply Removal/Installation.............................................. 6-86.9 Cooling Fan Removal/Installation ................................................ 6-96.10 Display PCB Removal/Installation................................................ 6-106.11 UIF PCB Removal/Installation...................................................... 6-116.12 Alarm Speaker Removal/Installation............................................ 6-13

Section 7: Spare Parts ............................................................................... 7-17.1 Introduction .................................................................................. 7-1

Section 8: Packing for Shipment .............................................................. 8-18.1 General Instructions ..................................................................... 8-18.2 Repacking in Original Carton ....................................................... 8-28.3 Repacking in a Different Carton................................................... 8-3

Table of Contents

iv

Section 9: Specifications........................................................................... 9-19.1 General ........................................................................................ 9-19.2 Electrical....................................................................................... 9-19.3 Physical Characteristics ............................................................... 9-29.4 Environmental .............................................................................. 9-29.5 Alarms .......................................................................................... 9-29.6 Factory Default Settings............................................................... 9-39.7 Performance ................................................................................ 9-3

Section 10: Serial Port Interface Protocol................................................ 10-110.1 Introduction .................................................................................. 10-110.2 Enabling the Serial Port................................................................ 10-110.3 Connecting to the Serial Port ....................................................... 10-110.4 Real-Time Printout ....................................................................... 10-210.5 Trend Data Printout...................................................................... 10-510.6 Nurse Call .................................................................................... 10-5

Section 11: Technical Supplement ........................................................... 11-111.1 Introduction .................................................................................. 11-111.2 Oximetry Overview....................................................................... 11-111.3 Circuit Analysis............................................................................. 11-211.4 Functional Overview..................................................................... 11-211.5 AC Input ....................................................................................... 11-311.6 Power Supply PCB Theory of Operation...................................... 11-311.7 Battery.......................................................................................... 11-411.8 User Interface PCB (UIF)............................................................. 11-511.9 Front Panel Display PCB and Controls ........................................ 11-811.10 Schematic Diagrams.................................................................... 11-8

Section 12: Index........................................................................................ 12-1

Table of Contents

v

LIST OF FIGURESFigure 1-1: NPB-195 Front Panel .................................................................. 1-2Figure 1-2: User Softkey Map........................................................................ 1-3Figure 1-3: NPB-195 Rear Panel................................................................... 1-4Figure 3-1: NPB-195 Controls ....................................................................... 3-2Figure 3-2: Self-Test Display......................................................................... 3-3Figure 3-3: Adjusting %SpO2 Upper Alarm Limit .......................................... 3-3Figure 3-4: Adjusting % SpO2 Lower Alarm Limit ......................................... 3-4Figure 3-5: Adjusting High Pulse Rate Alarm................................................ 3-4Figure 3-6: Adjusting Low Pulse Rate Alarm................................................. 3-4Figure 4-1: Service Function Softkeys........................................................... 4-2Figure 4-2: Service Function Softkey Map .................................................... 4-3Figure 4-3: Param Softkeys.......................................................................... 4-4Figure 4-4: Print Softkeys .............................................................................. 4-4Figure 4-5: Trend Printout ............................................................................. 4-5Figure 4-6: Errlog Printout ............................................................................. 4-6Figure 4-7: Instat Printout .............................................................................. 4-6Figure 4-8: Next Softkeys .............................................................................. 4-7Figure 4-9: Alarms Softkeys .......................................................................... 4-7Figure 6-1: Fuse Removal ............................................................................. 6-2Figure 6-2: NPB-195 Corner Screws............................................................. 6-3Figure 6-3: Separating Case Halves ............................................................. 6-4Figure 6-4: NPB-195 Battery ......................................................................... 6-5Figure 6-5: Internal Power Connections ........................................................ 6-6Figure 6-6: Power Entry Module ................................................................... 6-7Figure 6-7: Power Supply .............................................................................. 6-8Figure 6-8: Cooling Fan................................................................................. 6-9Figure 6-9: Display PCB ................................................................................ 6-10Figure 6-10: UIF PCB.................................................................................... 6-12Figure 6-11: Alarm Speaker .......................................................................... 6-13Figure 7-1: NPB-195 Expanded View............................................................ 7-2Figure 8-1: Repacking the NPB-195.............................................................. 8-2Figure 10-1: Serial Port Pin Layout................................................................ 10-2Figure 10-2: Real-Time Printout ................................................................... 10-2Figure 10-3: Trend Data Printout.................................................................. 10-5Figure 11-1: Oxyhemoglobin Dissociation Curve ......................................... 11-2Figure 11-2: NPB-195 Functional Block Diagram ......................................... 11-3Figure 11-3: UIF PCB Front End Red/IR Schematic Diagram ..................... 11-8Figure 11-4: Front End LED Drive Schematic Diagram ............................... 11-8Figure 11-5: Front End Output Schematic Diagram ..................................... 11-8Figure 11-6: Front End Power Supply Schematic Diagram.......................... 11-8Figure 11-7: Isolation Barrier EIA-232 Port Schematic Diagram.................. 11-8Figure 11-8: CPU Core Schematic Diagram A............................................. 11-9Figure 11-9: CPU Core Schematic Diagram B............................................. 11-9Figure 11-10: MC331 CPU Core Schematic Diagram A .............................. 11-9Figure 11-11: MC331 CPU Core Schematic Diagram B .............................. 11-9Figure 11-12: Display Driver Schematic Diagram ........................................ 11-9Figure 11-13: Speaker Driver Schematic Diagram....................................... 11-9Figure 11-14: Core Power Supply Schematic Diagram................................ 11-9Figure 11-15: Power On/Off Circuit Schematic Diagram ............................. 11-9Figure 11-16: UIF PCB Parts Locator Diagram............................................ 11-9Figure 11-17: Power Supply Schematic Diagram......................................... 11-9Figure 11-18: Power Supply Parts Locator Diagram .................................... 11-9

Table of Contents

vi

LIST OF TABLESTable 3-1: Dynamic Operating Range.......................................................... 3-7Table 3-2: Earth Leakage Current Limits ..................................................... 3-10Table 3-3: Enclosure Leakage Current Limits .............................................. 3-11Table 3-4: Patient Leakage Current Limits................................................... 3-11Table 3-5: Patient Leakage Current Test Configurations -

Mains Voltage on the Applied Part............................................. 3-12Table 4-1: Factory Default Settings .............................................................. 4-2Table 5-1: Problem Categories .................................................................... 5-2Table 5-2: Power Problems.......................................................................... 5-3Table 5-3: Button Problems.......................................................................... 5-4Table 5-4: Display/Alarms Problems ............................................................ 5-4Table 5-5: Operational Performance Problems............................................ 5-5Table 5-6: Serial Port Problems ................................................................... 5-6Table 5-7: Error Codes................................................................................. 5-7Table 7-1: Parts List ..................................................................................... 7-1Table 9-1: Default Settings ........................................................................... 9-3Table 10-1: Serial Port Pin-Outs................................................................... 10-1Table 10-2: Status Codes............................................................................. 10-4

1-1

SECTION 1: INTRODUCTION1.1 Manual Overview1.2 NPB-195 Pulse Oximeter Description1.3 Power-On Self Test1.4 Related Documents

1.1 MANUAL OVERVIEW

This manual contains information for servicing the Nellcor model NPB-195pulse oximeter. Only qualified service personnel should service this product.Before servicing the NPB-195, read the operator’s manual carefully for athorough understanding of operation.

WARNING: Explosion hazard. Do not use the NPB-195 pulse oximeter inthe presence of flammable anesthetics.

1.2 NPB-195 PULSE OXIMETER DESCRIPTION

The NPB-195 is a portable pulse oximeter intended for use as a continuousnoninvasive monitor of arterial oxygen saturation (SpO2) and pulse rate. It canbe used on adult, pediatric and neonatal patients. Oxygen saturation and pulserate are displayed digitally along with a plethysmographic waveform or a ten-segment blip bar which indicates pulse intensity.

Through the use of the four softkeys, the operator can access trend information,select an alarm limit to be changed, choose the language to be used, adjust theinternal time clock, and change communications protocol. The NPB-195 canoperate on AC power or on an internal battery. This monitor is intended for usein hospital, hospital-type facilities, during intra-hospital transport, and in homeenvironments. The controls and indicators for the NPB-195 are illustrated inFigure 1-1 through Figure 1-3.

Figure 1-2 illustrates the various functions available, and how to access them,through the use of the softkeys. A complete explanation of the keys is providedin the NPB-195 operator’s manual.

Section 1: Introduction

1-2

NPB-195

%SP02

BPM

100110

LIGHTLIMITS TREND SETUP

1 2 3 4 5 6 7 9

1011121415 13

8

16

1. SpO2 Sensor Port 9. Alarm Silence Button2. Low Battery Indicator 10. Adjust Up Button3. Power On/Standby Button 11. Adjust Down Button4. AC/Battery Charging Indicator 12. Contrast Button5. Waveform Display 13. Softkeys6. %SpO2 Indicator 14. Menu Bar7. Pulse Beats Per Minute display 15. Pulse Search Indicator8. Alarm Silence Indicator 16. Speaker

Figure 1-1: NPB-195 Front Panel


1-3

NormalDisplay Mode

Limits Trend Light

Sel Exit View Clock

Setup

ExitNext

ExitBlipPleth

Return to Display Mode

LCD Display LightON/OFF

View Zoom Next

Dual SpO2 Pulse Hist


Trend forSpO2 andPulse

SpO2 trendonly

Pulse trendonly

Histogram forSpO2 andPulse

Selects trend datafrom last 24, 12, 8, 4,2 or 1 hours 30min or15min

Exit

Clear Print

Yes No

Next

Clears alltrend info

Returns to prior trenddisplay

Print out of screen

Returns todisplaymode

Cycles between(Clear, Print, Exit,Next) screen and(View, Zoom,Exit, Next) screen

Exit

Select alarmlimit to be adjustedHigh/Low%SpO2 or Pulse

Comm Lang ExitNextSelect 24009600 or 19200

EnglishFrancaisDeutschItalianoEspanolDutchPortug

Return to Display


ExitSel

ExitSet

Mode

9565BPM

%SPO2

Figure 1-2: User Softkey Map


1-4

2

4

1 3

5

NPB-195

0123IPX1

R

NRTL/C

TM

T 0.50A 250V

2X

NELLCOR PURITAN BENNETT EUROPE BV,'s-HERTOGENBOSCH, THE NETHERLANDS

NELLCOR PURITAN BENNETT, INC.PLEASANTON, CA 94588, U.S.A.

MADE IN IRELAND

SN

100-120 V 200-240 V 50/60 Hz 20VA

U.S. PATENTS: 4,621,643; 4,653,498; 4,700,708; 4,770,179; 4,869,254; Re. 35,122; 4,928,692; 4,934,372; 5,078,136

CISPR 11Group 1Class B

1. Equipotential (ground) Terminal 4. Fuse Receptacle2. AC Inlet 5. Voltage Selection Switch3. DB-15 Interface Connector

Figure 1-3: NPB-195 Rear Panel

1.3 POWER-ON SELF TEST

When the NPB-195 is turned on it will perform a POST (Power-On Self Test).During POST the following sequence should occur:

• All indicator lights illuminate

• All pixels in the LCD display illuminate

• The backlight turns on and the Nellcor Puritan Bennett logo and softwareversion are displayed

Upon successful completion of POST, the NPB-195 sounds a 1-second toneindicating that the monitor has passed the test.

If the start-up sequence is not completed as described above, do not use themonitor.

The software version is often needed when calling Mallinckrodt's TechnicalServices Department or your local Mallinckrodt representative for technicalassistance. Record the software version and have it available prior to requestingtechnical assistance.

1.4 RELATED DOCUMENTS

To perform test and troubleshooting procedures, and to understand the principlesof operation and circuit analysis sections of this manual, you must know how tooperate the monitor. Refer to the NPB-195 operator’s manual. To understandthe various Nellcor sensors that work with the monitor, refer to the individualsensor’s directions for use.

2-1

SECTION 2: ROUTINE MAINTENANCE2.1 Cleaning2.2 Periodic Safety and Functional Checks2.3 Battery

2.1 CLEANING

Caution: Do not immerse the NPB-195 or its accessories in liquid or cleanwith caustic or abrasive cleaners. Do not spray or pour any liquid on themonitor or its accessories.

To clean the NPB-195, dampen a cloth with a commercial, nonabrasive cleanerand wipe the exterior surfaces lightly. Do not allow any liquids to come incontact with the power connector, fuse holder, or switches. Do not allow anyliquids to penetrate connectors or openings in the instrument cover. Wipe sensorcables with a damp cloth. For sensors, follow each sensor’s directions for use.

2.2 PERIODIC SAFETY AND FUNCTIONAL CHECKS

The following checks should be performed at least every 2 years by a qualifiedservice technician.

1. Inspect the exterior of the NPB-195 for damage.

2. Inspect safety labels for legibility. If the labels are not legible, contactMallinckrodt's Technical Services Department or your Mallinckrodtrepresentative.

3. Verify that the unit performs properly as described in paragraph 3.3.

4. Perform the electrical safety tests detailed in paragraph 3.4. If the unit failsthese electrical safety tests, do not attempt to repair the NPB-195. ContactMallinckrodt's Technical Services Department or your local Mallinckrodtrepresentative.

5. Inspect the fuses for proper value and rating (F1 & F2 = 0.5 amp slowblow).

2.3 BATTERY

Mallinckrodt recommends replacing the instrument battery every 2 years. Whenthe NPB-195 is going to be stored for 3 months or more, remove the battery priorto storage. To replace or remove the battery, refer to Section 6, DisassemblyGuide.

If the NPB-195 has been stored for more than 30 days, charge the battery asdescribed in paragraph 3.3.1. A fully discharged battery requires 14 hours instandby, or 18 hours if in use, to receive a full charge. The battery is beingcharged anytime the instrument is plugged into AC.

3-1

SECTION 3: PERFORMANCE VERIFICATION3.1 Introduction3.2 Equipment Needed3.3 Performance Tests3.4 Safety Tests

3.1 INTRODUCTION

This section discusses the tests used to verify performance following repairs orduring routine maintenance. All tests can be performed without removing theNPB-195 cover. All tests except the battery charge and battery performancetests must be performed as the last operation before the monitor is returned to theuser.

If the NPB-195 fails to perform as specified in any test, repairs must be made tocorrect the problem before the monitor is returned to the user.

3.2 EQUIPMENT NEEDED

Equipment DescriptionDigital multimeter (DMM) Fluke Model 87 or equivalent

Durasensor® oxygen transducer DS-100A

Oxisensor® II oxygen transducer D-25

Pulse oximeter tester SRC-2Safety analyzer Must meet current AAMI ES1/1993 &

IEC 601-1/1998 specificationsSensor extension cable EC-4 or EC-8Serial interface cable EIA-232 cable (optional)Stopwatch Manual or electronic

3.3 PERFORMANCE TESTS

The battery charge procedure should be performed before monitor repairswhenever possible. It should also be performed before returning the instrumentto use.

Note: This section is written using Mallinckrodt factory-set defaults. If yourinstitution has preconfigured custom defaults, those values will bedisplayed. Factory defaults can be restored using the configurationmode procedure described in paragraph 4.2.1 below.

Section 3: Performance Verification

3-2

3.3.1 Battery Charge

Perform the following procedure to fully charge the battery.

1. Connect the monitor to an AC power source.

2. Verify that the monitor is off and that the AC Power/Battery Chargingindicator is lit.

3. Charge the battery for at least 14 hours in standby.

3.3.2 Power-up Performance

The power-up performance tests (3.3.3.1 through 3.3.3.3) verify the followingmonitor functions:

• 3.3.2.1 Power-On Self-Test

• 3.3.2.2 Power-On Defaults and Alarm Limit Ranges

NPB-195

%SP02

BPM

100110

LIGHTLIMITS TREND SETUP

Power On/Standby Alarm silence

AdjustUp

AdjustDown

Soft keys Contrast

Figure 3-1: NPB-195 Controls

3.3.2.1 Power-On Self-Test

1. Connect the monitor to an AC power source and verify that the ACPower/Battery Charging indicator is lit.

2. Do not connect any input cables to the monitor.


3-3

3. Observe the monitor front panel. With the monitor off, press the PowerOn/Standby button. See Figure 3-1. The monitor must perform thefollowing sequence.

a. Within 2 seconds all LEDs are illuminated, then all pixels on the LCDdisplay are illuminated, after which, the backlight comes on.

b. The indicators remain lighted.

c. The LCD display shows the Nellcor Puritan Bennett logo and thesoftware version of the NPB-195 (Figure 3-2).

NPB-195

NellcorPuritanBennett

NPB-195 Version 1.1.0.5

Figure 3-2: Self-Test Display

d. A 1-second beep sounds indicating proper operation of the speaker, andall indicators turn off except the AC Power/Battery Chargingindicators.

e. The NPB-195 begins normal operation.

3.3.2.2 Power-On Defaults and Alarm Limit Ranges

Note: When observing or changing default limits, a 10-second timeout is ineffect. If no action is taken within 10 seconds, the monitorautomatically returns to the monitoring display.

Note: The descriptions that follow are based on the assumption that Pleth isthe view that has been selected. The steps to changing an alarm limitare the same if the view being used is Blip.

1. Ensure that the monitor is on. Press and release the Limits softkey. Verifythat the monitor emits a single beep and the plethysmograph waveform isreplaced with a display of the alarm limits. The high alarm limit for %SpO2will indicate an alarm limit of “100” inside a box (Figure 3-3).

NPB-195

EXITSEL

%SP02

BPM

100110

ALARM LIMITS

UPPERLOWER

SPO2 PULSE

8517040

100

Figure 3-3: Adjusting %SpO2 Upper Alarm Limit

At the end of 10 seconds, with no activity, normal monitoring is resumed.


3-4

2. Press the Limits softkey. Press and hold the Down Arrow button. Verifythat the boxed number for %SpO2 upper alarm limit reduces to a minimumof “85.”

Note: A decimal point in the display indicates that the alarm limits havebeen changed from factory default values.

3. Press the SEL softkey. Verify that the monitor emits a single beep and thebox moves to the %SpO2 lower alarm limit of “85.” See Figure 3-4.

NPB-195

EXITSEL

%SP02

BPM

100110

ALARM LIMITS

UPPERLOWER

SPO2 PULSE

8517040

100

Figure 3-4: Adjusting % SpO2 Lower Alarm Limit

4. Press and hold the Down Arrow button and verify that the %SpO2 loweralarm limit display reduces to a minimum of “20.” Press and hold the UpArrow button and verify that the %SpO2 lower alarm limit display cannot beraised past the upper alarm limit setting of “85.” Press the Exit button.

5. Press the Limits softkey and then press the SEL softkey two times. Verifythat the monitor emits a beep after each keystroke. The Pulse upper alarmlimit should be “170” and should be boxed. See Figure 3-5.

NPB-195

EXITSEL

%SP02

BPM

100110

ALARM LIMITS

UPPERLOWER

SPO2 PULSE

8517040

100

Figure 3-5: Adjusting High Pulse Rate Alarm

6. Press and hold the Down Arrow button. Verify that the Pulse upper alarmlimit display reduces to a minimum of “40” and is displayed. Press the Exitbutton.

7. Press the Limits softkey and then press the SEL softkey three times. Verifythat the Pulse lower alarm limit display indicates an alarm limit of “40” andis boxed. See Figure 3-6.

NPB-195

EXITSEL

%SP02

BPM

100110

ALARM LIMITS

UPPERLOWER

SPO2 PULSE

8517040

100

Figure 3-6: Adjusting Low Pulse Rate Alarm


3-5

8. Press and hold the Down Arrow button. Verify that the boxed Pulse loweralarm limit display reduces to a minimum of “30.”

9. Press and hold the Up Arrow button and verify that the boxed Pulse loweralarm limit display cannot be adjusted above the Pulse high limit of “40.”

10. Press the Power On/Standby button to turn the monitor off.

11. Press the Power On/Standby button to turn the NPB-195 back on.

12. Press and release the Limits softkey. Verify that the %SpO2 upper alarmlimit display is boxed and indicates an alarm limit of “100.”

13. Press the SEL softkey. Verify that the %SpO2 lower alarm limit display isboxed and indicates an alarm limit of “85.”

14. Press the SEL softkey a second time. Verify that the Pulse upper alarmlimit display is boxed and indicates an alarm limit of “170.”

15. Press the SEL softkey a third time. Verify that the Pulse lower alarm limitdisplay is boxed and indicates an alarm limit of “40.”

16. Press the Power On/Standby button to turn the monitor off.

3.3.3 Hardware and Software Tests

Hardware and software testing include the following tests.

• 3.3.3.1 Operation with a Pulse Oximeter Tester

• 3.3.3.2 General Operation

3.3.3.1 Operation with a Pulse Oximeter Tester

Operation with an SRC-2 pulse oximeter tester includes the following tests.

• 3.3.3.1.1 Alarms and Alarm Silence

• 3.3.3.1.2 Alarm Volume Control

• 3.3.3.1.3 Pulse Tone Volume Control

• 3.3.3.1.4 Dynamic Operating Range

3.3.3.1.1 Alarms and Alarm Silence

1. Connect the SRC-2 pulse oximeter tester to the sensor input cable andconnect the cable to the monitor. Set the SRC-2 as follows:

SWITCH POSITION

RATE 38

LIGHT LOW

MODULATION OFF

RCAL/MODE RCAL 63/LOCAL

2. Press the Power On/Standby button to turn the monitor on. After the normalpower-up sequence, press the following softkeys; Setup, View, and Pleth.Verify that the %SpO2 and Pulse initially indicate zeroes.


3-6

3. Move the modulation switch on the SRC-2 to LOW.

4. Verify the following monitor reactions:

a. The plethysmograph waveform begins to track the artificial pulsesignal from the SRC-2.

b. The pulse tone is heard.

c. Zeroes are displayed in the %SpO2 and Pulse displays.

d. After about 10 to 20 seconds, the monitor displays a saturation andpulse rate as specified by the tester. Verify that the values are withinthe following tolerances:

Oxygen Saturation Range 79% to 83%

Pulse Rate Range 37 to 39 bpm

e. The audible alarm sounds and both the %SpO2 and Pulse displays willflash, indicating both parameters have violated the default alarm limits.

5. Press and hold the Alarm Silence button on the front of the monitor for lessthan 2 seconds. Verify that the %SpO2 display indicates “60” and the Pulsedisplay indicates “SEC” while the Alarm Silence button is pressed. Whenthe button is released the alarm is silenced.

6. With the alarm silenced verify the following:

a. The alarm remains silenced.

b. The Audible Silence indicator lights.

c. The %SpO2 and Pulse displays continue to flash.

d. The pulse tone is still audible.

e. The audible alarm returns in approximately 60 seconds.

7. Press and hold the Alarm Silence button. Press the Down Arrow buttonuntil the Pulse display indicates “30.” Press the Up Arrow button and verifythat the displays indicate 60 SEC, 90 SEC, 120 SEC, and OFF. Release thebutton when the display indicates “OFF. "

8. Press and release the Alarm Silence button. Verify that the Alarm SilenceIndicator flashes.

9. Wait approximately 3 minutes. Verify that the alarm does not return. After3 minutes, the alarm silence reminder beeps three times, and will continueto do so at approximately 3-minute intervals.


3-7

3.3.3.1.2 Alarm Volume Control

After completing the procedure in paragraph 3.3.3.1.1 above:

1. Press and hold the Alarm Silence button and verify the following:

a. “OFF” is displayed for approximately 2 seconds.

b. After 2 seconds, a steady tone is heard at the default alarm volumesetting, the %SpO2 display indicates “VOL,” and the Pulse displayindicates the default setting of 5.

2. While still pressing the Alarm Silence button, press the Down Arrow buttonuntil an alarm volume setting of 1 is displayed. Verify that the volume ofthe alarm has decreased but is still audible.

3. Continue pressing the Alarm Silence button and press the Up Arrow buttonto increase the alarm volume setting to a maximum value of 10. Verify thatthe volume increases. Press the Down Arrow button until a comfortableaudio level is attained.

4. Release the Alarm Silence button. The tone will stop.

3.3.3.1.3 Pulse Tone Volume Control

1. Press the Up Arrow button and verify that the beeping pulse tone soundlevel increases.

2. Press the Down Arrow button and verify that the beeping pulse tonedecreases until it is no longer audible. Press the Up Arrow button to returnthe beep volume to a comfortable level.

3.3.3.1.4 Dynamic Operating Range

The following test sequence verifies proper monitor operation over a range ofinput signals.

1. Connect the SRC-2 to the NPB-195 and turn the NPB-195 on.

2. Place the SRC-2 in the RCAL 63/LOCAL mode.

3. Set the SRC-2 as indicated in Table 3-1. Verify that the NPB-195 readingsare within the indicated tolerances. Allow the monitor several seconds tostabilize the readings.

Note: A asterisk “*” indicates values that produce an alarm. Press the AlarmSilence button to silence the alarm.

Table 3-1: Dynamic Operating Range

SRC-2 Settings NPB-195 IndicationsRATE LIGHT MODULATION SpO2 Pulse Rate38 HIGH2 LOW 79 - 83* 35 - 41*112 HIGH1 HIGH 79 - 83* 109 - 115201 LOW LOW 79 - 83* 198 - 204*201 LOW HIGH 79 - 83* 198 - 204*


3-8

3.3.3.1.5 Nurse Call

Note: The Nurse Call tests must be performed with the instrument operatingon AC power.

1. Connect the negative lead of a voltmeter to pin 10 and positive lead to pin11 of the serial port on the back of the instrument (Figure 10-1). Ensurethat the audible alarm is not silenced or turned off.

2. Set the SRC-2 to create an alarm condition. Verify an output voltage at pins10 and 11 between +5 to +12 VDC.

3. Press the Alarm Silence button. With no active audible alarm, the outputvoltage at pins 10 and 11 must be between -5 to -12 VDC.

4. Turn the instrument off.

3.3.3.1.6 Operation on Battery Power

1. Turn the instrument on using AC Power.

2. Disconnect the instrument from AC and verify that the AC Power Indicatorturns off.

3. Verify that the instrument continues monitoring normally and that the LowBattery Indicator is not lit.

Note: If the Low Battery Indicator is illuminated, perform the procedureoutlined in step 3.3.1.

4. Connect the instrument to AC and verify that the AC Power Indicator turnson and that the instrument is monitoring normally.

3.3.3.2 General Operation

The following tests are an overall performance check of the system:

• 3.3.3.2.1 LED Excitation Test

• 3.3.3.2.2 Operation with a Live Subject

3.3.3.2.1 LED Excitation Test

This procedure uses normal system components to test circuit operation. ANellcor Oxisensor® II oxygen transducer, model D-25, is used to examine LEDintensity control. The red LED is used to verify intensity modulation caused bythe LED intensity control circuit.

1. Connect the monitor to an AC power source.

2. Connect an EC-4 or EC-8 sensor input cable to the monitor.

3. Connect a D-25 sensor to the sensor input cable.

4. Press the Power On/Standby button to turn the monitor on.

5. Leave the sensor open with the LEDs and photodetector visible.

6. After the monitor completes its normal power-up sequence, verify that thesensor LED is brightly lit.


3-9

7. Slowly move the sensor LED in proximity to the photodetector element ofthe sensor. Verify, as the LED approaches the optical sensor, that the LEDintensity decreases.

8. Open the sensor and notice that the LED intensity increases.

9. Repeat step 7 and the intensity will again decrease. This variation is anindication that the microprocessor is in proper control of LED intensity.

10. Turn the NPB-195 off.

3.3.3.2.2 Operation with a Live Subject

Patient monitoring involves connecting the monitor to a live subject for aqualitative test.

1. Ensure that the monitor is connected to an AC power source.

2. Connect an EC-4 or EC-8 sensor extension cable to the monitor.

3. Connect a Nellcor Durasensor® oxygen transducer, model DS-100A, to thesensor input cable.

4. Clip the DS-100A to the subject as recommended in the sensor’s directionsfor use.

5. Press the Power On/Standby button to turn the monitor on and verify thatthe monitor is operating.

6. The monitor should stabilize on the subject’s physiological signal in about15 to 30 seconds. Verify that the oxygen saturation and pulse rate arereasonable for the subject.

3.4 SAFETY TESTS

NPB-195 safety tests meet the standards of, and are performed in accordancewith, IEC 601-1 (EN 60601-1, Second Edition, 1988; Amendment 1, 1991-11,Amendment 2, 1995-03) and UL 2601-1 (August 18, 1994), for instrumentsclassified as Class 1 and TYPE BF and AAMI Standard ES1 (ANSI/AAMI ES11993).

• Ground Integrity

• Electrical Leakage

3.4.1 Ground Integrity

This test checks the integrity of the power cord ground wire from the AC plug tothe instrument chassis ground. The current used for this test is < 6V RMS 50 or60 Hz and 25 A.

1. Connect the monitor AC mains plug to the analyzer as recommended by theanalyzer operating instructions.

2. Connect the analyzer resistance input lead to the equipotential terminal(grounding lug) on the rear panel of the instrument. Verify that the analyzerindicates 100 milliohms or less.


3-10

3.4.2 Electrical Leakage

The following tests verify the electrical leakage of the monitor:

• Earth Leakage Current

• Enclosure Leakage Current

• Patient Applied Risk Current

• Patient Isolation Risk Current (Mains on Applied Part)

Note: For the following tests, ensure that the AC switch on the rear of theinstrument is configured for the AC voltage being supplied.

3.4.2.1 Earth Leakage Current

This test is in compliance with IEC 601-1 (earth leakage current) and AAMIStandard ES1 (earth risk current). The applied voltage for AAMI ES1 is 120VAC 60 Hz, for IEC 601-1 the voltage is 264 VAC 50 to 60 Hz. Allmeasurements shall be made with the power switch in both the “On” and “Off”positions. See Table 3-2.

1. Connect the monitor AC plug to the electrical safety analyzer asrecommended by the analyzer operating instructions.

2. The equipotential terminal is not connected to ground.

Table 3-2: Earth Leakage Current Limits

ACPOLARITY

LINECORD

NEUTRALCORD

LEAKAGECURRENT

Normal Closed Closed 500 µAReversed Closed Closed 500 µANormal Open Closed 1000 µANormal Closed Open 1000 µA

3.4.2.2 Enclosure Leakage Current

This test is in compliance with IEC 601-1 (enclosure leakage current) and AAMIStandard ES1 (enclosure risk current). This test is for ungrounded enclosurecurrent, measured between enclosure parts and earth. The applied voltage forAAMI/ANSI is 120 VAC 60 Hz, and for IEC 601-1 the applied voltage is 264VAC 50 to 60 Hz.

1. Connect the monitor AC plug to the electrical safety analyzer asrecommended by the analyzer operating instructions.

2. Place a 200-cm2 foil in contact with the instrument case, making sure thefoil is not in contact with any metal parts of the enclosure that may begrounded. Measure the leakage current between the foil and earth.

The analyzer leakage indication must not exceed values listed in Table 3-3:


3-11

Table 3-3: Enclosure Leakage Current Limits

AC LINECORD

NEUTRALLINE

CORD

POWERLINE

GROUNDCABLE

IEC 601-1 AAMI/ANSIES1

STANDARD

Closed Closed Closed 100 µA 100 µAClosed Closed Open 500 µA 300 µAClosed Open Closed 500 µA 300 µAOpen Closed Closed 500 µA 100 µAOpen Open Closed 500 µA 300 µAOpen Closed Open 500 µA 300 µA

3.4.2.3 Patient Applied Risk Current

This test is in compliance with AAMI Standard ES1 (patient applied riskcurrent), and IEC 601-1 (patient auxiliary current). The leakage current ismeasured between any individual patient connection and power (earth) ground.The applied voltage for AAMI/ANSI is 120 VAC 60 Hz, and for IEC 601-1 theapplied voltage is 264 VAC 50 to 60 Hz.

1. Configure the electrical safety analyzer as follows:

Function: Patient Leakage

Range: µA

2. Connect the monitor AC plug to the electrical safety analyzer asrecommended by the analyzer operating instructions for Patient LeakageCurrent.

3. Connect the patient leakage input lead of the electrical safety analyzer to allpins of the monitor's patient cable at the end of the cable.


5. All functional earth terminals are not connected to ground.

6. Measure the leakage current between the patient connector and earth. SeeTable 3-4.

Table 3-4: Patient Leakage Current Limits

AC LINEPOLARITY

NEUTRALLINE

POWERLINE

GROUNDCABLE


STANDARD

Normal Closed Closed 100 µA 10 µANormal Open Closed 500 µA 50 µANormal Closed Open 500 µA 50 µAReverse Closed Closed 100 µA 10 µAReverse Open Closed 500 µA 50 µAReverse Closed Open 500 µA 50 µA


3-12

3.4.2.4 Patient Isolation Risk Current - (Mains Voltage on the Applied Part)

This test is in compliance with AAMI Standard ES1 (patient isolation riskcurrent [sink current]), and IEC 601-1 (patient leakage current). Patient LeakageCurrent is the measured value in a patient connection if mains voltage isconnected to that patient connection. The applied voltage for AAMI/ANSI is120 VAC 60 Hz, and for IEC 601-1 the applied voltage is 264 VAC 50 to 60 Hz.

Warning: AC mains voltage will be present on the patient applied partterminals during this test. Exercise caution to avoid electrical shock hazard.

1. Configure the electrical safety analyzer as follows:

Function: Patient Leakage (Mains On Applied Part)

Range: µA

2. Connect the monitor AC plug to the electrical safety analyzer asrecommended by the operating instructions for patient sink (leakage)current.

3. Connect the patient leakage input lead to the electrical safety analyzer to allconnectors in the patient cable at the patient end of the cable.


5. All functional earth terminals are not connected to ground.

6. The analyzer leakage current must not exceed the values shown inTable 3-5.

Table 3-5: Patient Leakage Current Test Configurations -Mains Voltage on the Applied Part

AC LINEPOLARITY

NEUTRALLINE

POWERLINE

GROUNDCABLE


STANDARD

Normal Closed Closed 5 mA 50 µAReverse Closed Closed 5 mA 50 µA

4-1

SECTION 4: POWER-ON SETTINGS AND SERVICE FUNCTIONS4.1 Introduction4.2 Power-on Settings4.3 Service Functions

4.1 INTRODUCTION

This section discusses how to reconfigure power-on default values, access theservice functions, and set the clock.

4.2 POWER-ON SETTINGS

The following paragraphs describe how to change power-on default settings.

Through the use of softkeys shown in Figure 1-2, the user can change alarmlimits, the type of display, baud rate, time and date, and trends to view. Adecimal point is added to the right of a display when the alarm limit for thatdisplay has been changed to a value that is not a power-on default value. If thenew value is saved as a power-on default value, the decimal point will beremoved. By using the service functions, changes can be saved as power-ondefault values.

Some values cannot be saved as power-on default values. An SpO2 Low limitless than 80 will not be saved as a power-on default. Audible Alarm Off will notbe accepted as a power-on default. An attempt to save either of these values as adefault will result in an invalid tone. Both values can be selected for the currentpatient, but they will be lost when the instrument is turned off.

4.2.1 Factory Default Settings

Factory default settings for the NPB-195 are listed in Table 4-1. Refer to theOperator's manual for changing the parameters listed in Table 4-1. Set desiredparameter limits as desired. Refer to paragraph 4-3 to apply these newparameters as default parameters.

Section 4: Power-On Settings and Service Functions

4-2

Table 4-1: Factory Default Settings

Parameter Default ValueSpO2 High 100%SpO2 Low 85%Pulse Rate High 170 bpmPulse Rate Low 40 bpmAlarm Volume Level 5Alarm Silence Duration 60 secondsAlarm Silence Restriction Sound ReminderPulse Beep Volume Level 4Baud Rate 9600Display PlethTrend SaturationContrast Mid-rangeLanguage English

4.3 SERVICE FUNCTIONS

4.3.1 Introduction

Service functions can be used to select institutional defaults, and to accessinformation about the patient or instrument. Only a Mallinckrodt CustomerService Engineer should access some of the items available through the servicefunctions. These functions will be described in the text to follow.

4.3.2 Accessing the Service Functions

All service functions are accessible only if the sensor cable is disconnected fromthe instrument. Simultaneously press the 4th softkey from the left and thecontrast button for more than 3 seconds. The menu bar will change to theheadings listed in Figure 4-1.

Note: If a “Sensor Disconnected” prompt appears on the screen, press theAlarm Silence button and repeat the above procedure.

Note: If the above steps are performed with a sensor cable connected, only theParam and Exit softkeys appear on the screen.

NPB-195

NEXTPARAM PRINT EXIT

%SP02

BPM- - -- - -

Figure 4-1: Service Function Softkeys


4-3

Figure 4-2 can be used as a quick reference showing how to reach differentsoftkey functions. Items reached through the Param softkey can be accessedduring normal operation. Functions provided by the Print and Next softkeyscannot be accessed when a sensor cable is connected to the instrument. Each ofthe various functions is described in the text to follow.

Param Print Next

Reset

Downld Alarms Next

Trend Errlog Instat Info

Exit

Save

Yes No

Yes No

ExitSel

Exit

Exit

Contrast Paragraph 4.3.2.1 Paragraph 4.3.2.2 Paragraph 4.3.2.3

Paragraph 4.3.2.1 and 4.3.2.4

BPM

Figure 4-2: Service Function Softkey Map

4.3.2.1 Exit & Next Softkeys

NEXT

There are not enough buttons to display all of the options that are available atsome levels of the menu. Pressing the Next button allows you to view additionaloptions available at a given menu level.

EXIT

To back up one menu level, press the Exit button. The service functions can beexited by repeatedly pressing the Exit button.

4.3.2.2 Param

When the Param softkey is pressed, the function of the softkeys changes asshown in Figure 4-3. These options can be accessed without disconnecting thesensor cable from the instrument.


4-4

NPB-195

RESET SAVE EXIT

%SP02

BPM- - -- - -

Figure 4-3: Param Softkeys

RESET

The Reset button can be used if alarm values stored in memory have beenchanged from factory default values. If Yes is pressed, the instrument soundsthree tones and the alarm limits return to factory default values. When No ispressed, no changes are made to the values stored in memory.

SAVE

When adjustable values are changed from factory default, the Save button can beused to preserve the settings as institutional power-on default values. PressingYes stores the current settings in memory. The instrument sounds three tonesindicating that the change has been saved as power-on default values. If aninvalid tone is sounded, the parameter cannot be saved as a power-on default(see paragraph 4.2).

These values will continue to be used through power-on and -off cycles untilthey are changed and saved again, or until they are reset. If No is pressed, thechanged values will not be saved.

4.3.2.3 Print

PRINT

Accessing the Print softkey makes three printouts available. See Section 10 forinformation about how to make connections to the serial port and how data ispresented in a printout. The appropriate printout can be selected by pressing thecorresponding softkey. Figure 4-4 represents the softkey configuration after thePrint softkey has been selected.

Up to 24 hours of data can be retrieved from the printouts described below.When the instrument is turned on, a line of data is recorded every 5 seconds. Asan example, an instrument that is used 6 hours a week would take 4 weeks to fillits memory.

Note: The two-letter codes and the symbols that occur in the printout aredescribed in Table 10-2.

NPB-195

NEXTTREND ERRLOG EXIT

%SP02

BPM- - -- - -

Figure 4-4: Print Softkeys


4-5

TREND

A Trend printout will include all data recorded for up to 24 hours of monitoringsince the last Clear data was performed. A trend line is recorded every 5seconds or whenever an alarm condition has occurred. Figure 4-5 is an exampleof a Trend printout.

NPB-195 Version 1.0.0.000 TREND SpO2 Limit: 30-100% PR Limit: 100-180 bpm

TIME %SpO2 PR (bpm) PA

01-Jul-97 14:00:00 100 120 220

01-Jul-97 14:00:05 100 124 220

01-Jul-97 14:00:10 100 190 220

01-Jul-97 14:00:15 100 190 220

01-Jul-97 18:00:43 - - - - - - - - -

01-Jul-97 18:00:48 - - - - - - - - -

NPB-195 Version 1.0.0.000 Trend SpO2 Limit: 80-100% PR Limit: 60-180 bpm

Time %SpO2 PR (bpm) PA

01-Jul-97 18:00:53 - - - - - - - - -

01-Jul-97 18:00:58 - - - - - - - - -

01-Jul-97 18:01:03 98 100 140

01-Jul-97 18:01:08 98 181* 190

01-Jul-97 18:01:13 99 122 232

Output Complete

Figure 4-5: Trend Printout

The first two lines are the column heading lines. The first line includesinformation about the type of instrument delivering the information, the softwarelevel, type of printout, and alarm parameters. The second line consists of thecolumn headings These lines are printed out every 25 lines or when a change toan alarm parameter is made. Patient data is represented with a date and timestamp for the data. In the example above, the “- - -” means that a sensor wasconnected but no data was being received (patient disconnect). Patient data thatis outside of an alarm limit is marked with an asterisk (*).

At the end of the printout “Output Complete” will be printed. This indicates thatthere was no corruption of data. If the Output Complete statement is not printedat the end of the printout, the data must be considered invalid.

ERRLOG

A list of all the errors recorded in memory can be obtained by pressing theErrlog softkey. The first line the type of instrument producing the printout,software level, type of printout and the time of the printout. The second line liststhe column headings. An example of an Errlog printout is shown in Figure 4-6.


4-6

NPB-195 Version 1.0.0.000 Error Log Time: 14600:00:07

Op Time Error Task Addr Count

10713:21:03 52 12 48F9 100

00634:26:01 37 4 31A2 3

Output Complete

Figure 4-6: Errlog Printout

INSTAT

A Delete softkey, described in the Operator's manual, allows the user to clear themost recent trend data. Cleared trends can still be retrieved from the instrumentthrough an Instat printout. Instat can be accessed by pressing Next after the Printsoftkey has been selected.

The oldest cleared trend will become Trend 01 on the Instat printout. If a Trend01 already existed in memory from an earlier Clear, the next clear will becomeTrend 02. Every time a Clear is performed from the User Softkeys, the numberof existing trends will increase by 1.

Figure 4-7 illustrates an Instat printout. The first line is for instrument type,software revision level, type of printout, and alarm parameter settings. Thesecond line lists the column headings. A line of data is recorded for every 5seconds of instrument operation. Up to 24 hours of instrument operation datacan be recorded.

The final line on the printout is Output Complete. This indicates that data hasbeen successfully transmitted with no corruption. If no Output Complete line isprinted, the data should be considered invalid.NPB-195 Version 1.0.0.000 Instrument SpO2 Limit: 30-100% PR Limit: 100-180 bpmTIME Trend 01 %SpO2 PR (bpm) PA SpO2 Status UIF Status Aud01-Jul-97 14:00:00 - - - - - - - - - SD BU LB AO L01-Jul-97 14:00:05 - - - - - - - - - PS BU LB AO01-Jul-97 14:00:10 100 120 220 BU LB01-Jul-97 14:00:15 100 120 220 BU LBNPB-195 Version 1.0.0.000 Instrument SpO2 Limit: 80-100% PR Limit: 60-180 bpmTIME Trend 01 %SpO2 PR (bpm) PA SpO2 Status UIF Status Aud01-Jul-97 14:24:24 79* 58* 220 PS SL PL BU LB M01-Jul-97 14:24:29 79* 57* 220 PS SL PL BU LB AS M01-Jul-97 14:24:29 0* 0* - - - PS LP SL PL BU LB AS HNPB-195 Version 1.0.0.000 Instrument SpO2 Limit: 80-100% PR Limit: 60-180 bpmTIME Trend 01 %SpO2 PR (bpm) PA SpO2 Status UIF Status Aud11-Jul-97 7:13:02 99 132* 220 PH BU M11-Jul-97 7:13:07 99 132* 220 PH BU M11-Jul-97 7:13:12 99 132* 220 PH BU M11-Jul-97 7:13:17 99 132* 220 PH BU M11-Jul-97 7:13:22 99 132* 220 PH BU M11-Jul-97 7:13:27 99 132* 220 PH BU M11-Jul-97 7:13:32 99 132* 220 PH BU MOutput Complete

Figure 4-7: Instat Printout


4-7

4.3.2.4 Next

Additional options can be accessed from the main Service Functions menu bypressing the Next softkey. When Next is pressed, the softkeys change to thefunctions shown in Figure 4-8.

NPB195

DOWNLD ALARMS EXIT NEXT

BPM

Figure 4-8: Next Softkeys

DOWNLD

When Downld is selected, the instrument will display the revision of the BootCode. To exit Downld, cycle power to the instrument by pressing the PowerOn/Standby button.

ALARMS

Pressing the Alarms softkey can change characteristics of the audible alarm.When the Alarms softkey is pressed, the softkey’s functions change as shown inFigure 4-9.

NPB-195

SEL EXIT

%SP02

BPM- - -- - -

Figure 4-9: Alarms Softkeys

SEL

The Sel softkey is used to select what function of the audible alarm is going tobe changed. A box can be cycled between two choices: Allow and Reminder.

When Allow is selected, a choice is given between allowing an audible alarm offor disabling the audible alarm off. Pressing the Up or Down arrow key cyclesbetween yes and no. If Yes is selected, the operator has the option of selectingAudible Alarm Off. If No is selected, the operator will not be given the optionof selecting Audible Alarm Off.

If the audible alarm is disabled or silenced, a reminder tone can be soundedevery three minutes to notify the user of this condition. The Up and Down arrowkeys can be used to change the choice from Yes to No. Selecting Yes enablesthe Reminder and No disables the Reminder.

5-1

SECTION 5: TROUBLESHOOTING5.1 Introduction5.2 How to Use this Section5.3 Who Should Perform Repairs5.4 Replacement Level Supported5.5 Obtaining Replacement Parts5.6 Troubleshooting Guide5.7 Error Codes

5.1 INTRODUCTION

This section explains how to troubleshoot the NPB-195 if problems arise.Tables are supplied that list possible monitor difficulties, along with probablecauses, and recommended actions to correct the difficulty.

5.2 HOW TO USE THIS SECTION

Use this section in conjunction with Section 3, Performance Verification, andSection 7, Spare Parts. To remove and replace a part you suspect is defective,follow the instructions in Section 6, Disassembly Guide. The circuit analysissection in the Technical Supplement offers information on how the monitorfunctions.

5.3 WHO SHOULD PERFORM REPAIRS

Only qualified service personnel should open the monitor housing, remove andreplace components, or make adjustments. If your medical facility does not havequalified service personnel, contact Mallinckrodt's Technical Services or yourlocal Mallinckrodt representative.

5.4 REPLACEMENT LEVEL SUPPORTED

The replacement level supported for this product is to the printed circuit board(PCB) and major subassembly level. Once you isolate a suspected PCB, followthe procedures in Section 6, Disassembly Guide, to replace the PCB with aknown good PCB. Check to see if the trouble symptom disappears and that themonitor passes all performance tests. If the trouble symptom persists, swap backthe replacement PCB with the suspected malfunctioning PCB (the original PCBthat was installed when you started troubleshooting) and continuetroubleshooting as directed in this section.

5.5 OBTAINING REPLACEMENT PARTS

Mallinckrodt's Technical Services provides technical assistance information andreplacement parts. To obtain replacement parts, contact Mallinckrodt'sTechnical Services Department or your local Mallinckrodt representative. Referto parts by the part names and part numbers listed in Section 7, Spare Parts.

Section 5: Troubleshooting

5-2

5.6 TROUBLESHOOTING GUIDE

Problems with the NPB-195 are separated into the categories indicated inTable 5-1. Refer to the paragraph indicated for further troubleshootinginstructions.

Note: Taking the recommended actions discussed in this section will correctthe majority of problems you may encounter. However, problems notcovered here can be resolved by calling Mallinckrodt's TechnicalServices Department or your local Mallinckrodt representative.

Table 5-1: Problem Categories

Problem Area Refer to Paragraph1. Power• No power-up on AC and/or DC• Fails power-on self-test• Powers down without apparent cause

5.6.1

2. Buttons• Monitor does not respond properly to

buttons

5.6.2

3. Display/Alarms• Displays do not respond properly• Alarms or other tones do not sound

properly or are generated withoutapparent cause

5.6.3

4. Operational Performance• Displays appear to be operational, but

monitor shows no readings• Suspect readings

5.6.4

5. Serial Port• NPB-195 serial port not functioning

properly

5.6.5


5-3

5.6.1 Power

Power problems are related to AC and/or DC. Table 5-2 lists recommendedactions to resolve power problems.

Table 5-2: Power Problems

Condition Recommended Action1. Battery Low

indicator lightssteadily whileNPB-195 isconnected to ACand battery isfully charged.

1. Ensure that the NPB-195 is plugged into anoperational AC outlet and the AC indicator is on.

2. Check the fuses. The fuses are located in the PowerEntry Module as indicated in paragraph 6.3 andFigure 6-1 of the Disassembly Guide. Replace ifnecessary.

3. Open the monitor as described in section 6. Verifythe power supply’s output to the battery while on AC.Disconnect the battery leads from the battery andconnect a DVM to them. The voltage measuredshould be 6.80 VDC ± 0.15 VDC, and the currentshould be 400 mA ± 80 mA. Replace power supply ifabove values are not met.

4. Check the ribbon connection from the bottomenclosure to the UIF PCB, as instructed in paragraph6.11 of the Disassembly Guide section. If theconnection is good, replace the UIF PCB.

2. The NPB-195does not operatewhendisconnectedfrom AC power.

1. The battery may be discharged. To recharge thebattery, refer to paragraph 3.3.1, Battery Charge. Themonitor may be used with a less than fully chargedbattery but with a corresponding decrease inoperating time from that charge.

2. If the battery fails to hold a charge, replace the batteryas indicated in Section 6, Disassembly Guide.

3. Battery Lowindicator onduring DCoperation and analarm issounding.

There are 15 minutes or less of usable charge left on theNPB-195 battery before the instrument shuts off. At thispoint, if possible, cease use of the NPB-195 on batterypower, connect it to an AC source and allow it torecharge (approximately 14 hours). The NPB-195 maycontinue to be used while it is recharging. (A fullrecharge of the battery while the monitor is being usedtakes 18 hours.)

4. Battery does notcharge.

1. Replace battery if more than 2 years old.2. Open the monitor as described in Section 6. Verify

the power supply’s output to the battery while on AC.Disconnect the battery leads from the power supplyand connect a DVM to them. The voltage measuredshould be 6.8 VDC ± 0.15 and the current should be400 mA ± 80 mA. Replace power supply if abovevalues are not met.


5-4

5.6.2 Buttons

Table 5-3 lists symptoms of problems relating to non-responsive buttons andrecommended actions. If the action requires replacement of a PCB, refer toSection 6, Disassembly Guide.

Table 5-3: Button Problems

Condition Recommended Action1. The NPB-195 responds

to some, but not allbuttons.

1. Replace Top Housing assembly.2. If the buttons still do not work, replace the UIF

PCB.2. The NPB-195 turns on

but does not respond toany of the buttons.

1. Replace Top Housing assembly.2. If the buttons still do not work, replace the UIF

PCB.

5.6.3 Display/Alarms

Table 5-4 lists symptoms of problems relating to non-functioning displays,audible tones or alarms, and recommended actions. If the action requiresreplacement of a PCB or module, refer to Section 6, Disassembly Guide.

Table 5-4: Display/Alarms Problems

Condition Recommended Action1. Display values are

missing or erratic.1. If the sensor is connected, replace the sensor

connector assembly.2. If the condition persists, replace the sensor

extension cable.3. If the condition still persists, replace the UIF

PCB.2. Display pixels do not

light.1. Check the connection between the UIF PCB and

the Display PCB.2. If the condition does not change, replace the

Display PCB.3. If the condition still persists, replace the UIF

PCB.3. Alarm sounds for no

apparent reason.1. Moisture or spilled liquids can cause an alarm to

sound. Allow the monitor to dry thoroughlybefore using.

2. If the condition persists, replace the UIF PCB.4. Alarm does not sound. 1. Replace the speaker as described in Section 6,

Disassembly Guide.2. If the condition persists, replace the UIF PCB.


5-5

5.6.4 Operational Performance

Table 5-5 lists symptoms of problems relating to operational performance (noerror codes displayed) and recommended actions. If the action requiresreplacement of a PCB or module, refer to Section 6, Disassembly Guide.

Table 5-5: Operational Performance Problems

Condition Recommended Action1. The Pulse AMPLITUDE

indicator seems toindicate a pulse, but thedigital displays showzeroes.

1. The sensor may be damaged; replace it.2. If the condition still persists, replace the UIF

PCB.

2. SpO2 or Pulse valueschange rapidly; PulseAMPLITUDE indicator iserratic.

1. The sensor may be damp or may have beenreused too many times. Replace it.

2. An electrosurgical unit (ESU) may beinterfering with performance:

– Move the NPB-195 and its cables and sensorsas far from the ESU as possible.

– Plug the NPB-195 power supply and the ESUinto different AC circuits.

– Move the ESU ground pad as close to thesurgical site as possible and as far away fromthe sensor as possible.

3. Verify the performance with the proceduresdetailed in Section 3.

4. If the condition still persists, replace the UIFPCB.


5-6

5.6.5 Serial Port

Table 5-6 lists symptoms of problems relating to the serial port andrecommended actions. If the action requires replacement of the PCB, refer toSection 6, Disassembly Guide.

Table 5-6: Serial Port Problems

Condition Recommended Action1. No printout is being

received1. The unit is running on battery power.

Connect to an AC source.2. The monitor’s baud rate does not match the

printer. Change the baud rate of the monitorfollowing instructions in paragraph 10.2.


2. The nurse call is notworking.

1. The unit is running on battery power.Connect to an AC source.

2. Verify connections are made between pins 10(GND) and 11 (nurse call) of the serial port.

3. Verify output voltage between ground pin 10and pin 11 is -3 to -10 VDC (no alarm) and+3 to +10 VDC (during alarm)



5-7

5.7 ERROR CODES

An error code is displayed when the NPB-195 detects a non-correctable failure.When this occurs, the unit will stop monitoring, sound a low priority alarm thatcannot be silenced, clear patient data from the display, and display an error code.Table 5-7 provides a complete list of error codes and possible solutions.

Table 5-7: Error Codes

Code Meaning Possible Solutions1 POST failure Replace UIF PCB4 Battery dead 1. Check the voltage selector

switch.2. Charge battery for 14 hours3. Leads of battery reversed (see paragraph 6.6)4. Replace battery

5 Too many microprocessor resetswithin a period of time

1. Cycle power2. Replace UIF PCB if code 5 repeatedly occurs3. Replace Power Supply

6 Boot CRC error Replace UIF PCB7 Error on UIF PCB 1. Cycle power to clear error.

2. Check voltage selector switch for proper setting.3. Replace UIF PCB

11 Flash ROM corruption Replace UIF PCB76 Error accessing EEPROM Replace UIF PCB80 Institutional default values lost

and reset to factory defaultvalues

1. Cycle power2. Replace UIF PCB if code 80 repeatedly occurs

82 Time clock lost 1. Reset time clock2. Battery power was lost; check the battery3. Replace the Power Supply

84 Internal communications error Replace UIF PCB

6-1

SECTION 6: DISASSEMBLY GUIDE6.1 Introduction6.2 Prior to Disassembly6.3 Fuse Replacement6.4 Monitor Disassembly6.5 Monitor Reassembly6.6 Battery Replacement6.7 Power Entry Module Removal/Installation6.8 Power Supply Removal/Installation6.9 Cooling Fan Removal/Installation6.10 Display PCB Removal/Installation6.11 UIF PCB Removal/Installation6.12 Alarm Speaker Removal/Installation

6.1 INTRODUCTION

The NPB-195 can be disassembled down to all major component parts,including:

• PCBs

• battery

• cables

• chassis enclosures

The following tools are required:

• small, Phillips-head screwdriver

• medium, Phillips-head screwdriver

• small blade screwdriver

• needle-nose pliers or 1/4-inch socket

• torque wrench, 10 inch-pounds (1.13 newton-meters)

WARNING: Before attempting to open or disassemble the NPB-195,disconnect the power cord from the NPB-195.

Caution: Observe ESD (electrostatic discharge) precautions when workingwithin the unit.

Note: Some spare parts have a business reply card attached. When youreceive these spare parts, please fill out and return the card.

6.2 PRIOR TO DISASSEMBLY

1. Turn the NPB-195 Off by pressing the Power On/Standby button.

2. Disconnect the monitor from the AC power source.

Section 6: Disassembly Guide

6-2

6.3 FUSE REPLACEMENT

1. Complete procedure in paragraph 6.2.

2. Disconnect the power cord from the back of the monitor.

3. Remove the fuse drawer from the power module by pressing down on thetab in the center and pulling out as shown in Figure 6-1.

Figure 6-1: Fuse Removal

4. Put new fuses of equivalent size and rating in the drawer and reinsert thedrawer in the power module.


6-3

6.4 MONITOR DISASSEMBLY

1. Set the NPB-195 upside down, as shown in Figure 6-2.

Corner screws

Figure 6-2: NPB-195 Corner Screws

2. Remove the four corner screws.

Caution: Observe ESD (electrostatic discharge) precautions whendisassembling and reassembling the NPB-195 and when handling any of thecomponents of the NPB-195.

3. Separate the top case from the bottom case of the monitor, being careful notto stress the wire harnesses between the cases. Place the two halves of themonitor on the table as shown in Figure 6-3.

4. Disconnect the Power Supply from J6 on the UIF PCB.


6-4

J6

Power supplyharness

Figure 6-3: Separating Case Halves

6.5 MONITOR REASSEMBLY

1. Connect the Power Supply to J6 on the UIF PCB.

2. Place the top case over the bottom case, being careful to align the lens,Power Entry Module, and the fan with the slots in the top case.

Caution: When reassembling the NPB-195, tighten the screws that hold thecases together to a maximum of 10 inch-pounds. Over-tightening couldstrip out the screw holes in the top case, rendering it unusable.

3. Install the four corner screws.


6-5

6.6 BATTERY REPLACEMENT

Removal

1. Follow the procedure in paragraphs 6.2 and 6.4.

2. Remove the two screws from the battery bracket and lift the battery out ofthe bottom case as shown in Figure 6-4.

3. Be sure to note the polarity of the leads. Use needle-nose pliers todisconnect the leads from the battery.

Figure 6-4: NPB-195 Battery

4. The lead-acid battery is recyclable. Do not dispose of the battery by placingit in the regular trash. Dispose of battery in accordance with localregulations or return to Mallinckrodt's Technical Services Department fordisposal.

Installation

5. Connect the leads to the battery. The red wire connects to the positiveterminal, and the black wire connects to the negative terminal. SeeFigure 6-5.

6. Insert the new battery into the bottom case with the negative terminaltowards the outside of the monitor. Install the bracket and grounding leadwith the two screws.


6-6

W1to

EquipotentialLug

W2to

"L" onPEM

W3to

"N" on PEM

W5 -Black

W4 + Red

EquipotentialLug

J1

Figure 6-5: Internal Power Connections

7. Complete the procedure in paragraph 6.5.

8. Turn the monitor on and verify proper operation.


6-7

6.7 POWER ENTRY MODULE (PEM) REMOVAL/INSTALLATION

Removal

1. Complete the procedures in paragraphs 6.4.

2. Push the top of the Power Entry Module (PEM) in from the outside of thecase, and lift up.

3. Use needle-nose pliers to disconnect the leads from the PEM(see Figure 6-6).

G

L

N

Figure 6-6: Power Entry Module

Installation

4. Reconnect the three leads. The blue wire from W3 on the power supplygoes to the terminal labeled “N” on the PEM. The brown wire from W2 onthe power supply connects to the terminal labeled “L.” The center terminal(labeled "G") at the top of the PEM is for the ground wire (Figure 6-6).

5. Install the PEM in the bottom case with the fuse drawer facing down. A tabin the bottom case holds the PEM in place. Insert the bottom wing of thePEM between the tab and the internal edge of the side wall of the bottomcase. Push the PEM down and towards the outside of the monitor until itclicks into place.


6-8

6. Position the AC lines from the PEM so that they do not come into contactwith components on the Power Supply PCB.


6.8 POWER SUPPLY REMOVAL/INSTALLATION

Removal

1. Complete the procedures in paragraphs 6.2 and 6.4.

2. Complete steps 2 through 4 in paragraph 6.7.

3. Disconnect the fan wire harness from J1 on the Power Supply PCB (seeFigure 6-5).

4. Use a 10-mm wrench to disconnect the Power Supply ground lead from theequipotential lug (Figure 6-5).

5. Remove the seven screws shown in Figure 6-7.

Figure 6-7: Power Supply

6. Lift the Power Supply out of the bottom case.

Installation

7. Place the Power Supply in the bottom case.

Caution: When installing the Power Supply, tighten the seven screws to amaximum of 4 inch-pounds. Over-tightening could strip out the screw holesin the bottom case, rendering it unusable.


6-9

8. Install the seven screws in the Power Supply and tighten.

9. Connect the fan harness to J1 on the Power Supply.



6.9 COOLING FAN REMOVAL/INSTALLATION

Removal


2. Disconnect the fan wire harness from J1 on the Power Supply PCB (seeFigure 6-5).

3. Lift the cooling fan from the slots in the bottom case (see Figure 6-8).

J1

Figure 6-8: Cooling Fan

Installation

4. Insert the cooling fan into the slots in the bottom case with the padded sideson the top and bottom and the fan’s harness to the handle side of the case.

5. Connect the cooling fan wire harness to J1 on the Power Supply PCB.

6. Complete procedure 6-5.


6-10

6.10 DISPLAY PCB REMOVAL/INSTALLATION

Removal

Note: The LCD panel contains toxic chemicals. Do not ingest chemicals from abroken LCD panel.

1. Complete procedures 6.2 and 6.4.

2. Disconnect the CCFL harness (two white wires) from J5 of the UIF PCB.See Figure 6-9.

3. Use a small blade screwdriver to pry the clip from either edge of J9, thendisconnect the Display PCB ribbon cable from the connector.

4. Remove the screw holding the clamp to the ferrite on the ribbon cable of theDisplay PCB.

Speaker wires to J13on the UIF PCB

Keypad ribbon cableto J8 on UIF PCB

Display ribbon cableto J9 on UIF PCB

CCFL wires to J5on the UIF PCB

Double-SidedTape

Figure 6-9: Display PCB


6-11

5. Separate the adhesive connection of the double-sided tape and lift theDisplay PCB up to remove it from the top case.

6. Remove the used double-sided tape.

Installation

7. Install new double-sided tape located as shown in Figure 6-9.

8. Slide the Display PCB into the grooves in the top case. Apply pressurebetween the top case and the display PCB to make good contact with thedouble-sided tape.

9. Connect the wire harness with two white wires to J5 of the UIF PCB.

10. Connect the Display PCB ribbon cable to J9 of the UIF PCB. Install theclip over the J9 connector.

11. Secure the ferrite on the ribbon cable from the Display PCB. Place theclamp over the ferrite and screw the clamp to the UIF PCB.


6.11 UIF PCB REMOVAL/INSTALLATION

Removal



3. Disconnect the keypad ribbon cable from J8 of the UIF PCB (Figure 6-9).J8 is a ZIF connector. Lift up on the outer shell until it clicks, then removethe ribbon cable from the connector.

4. Disconnect the speaker cable from J13 on the UIF PCB.

5. Remove the five screws in the UIF PCB. See Figure 6-10.

6. Remove the UIF PCB from the top case.


6-12

Figure 6-10: UIF PCB

Installation

Caution: When installing the UIF PCB, hand tighten the five screws to amaximum of 4 inch-pounds. Over-tightening could strip out the screw holesin the top case, rendering it unusable.

7. Place the UIF PCB in the top case.

8. Install the four screws in the UIF PCB.

9. Lift up on the outer shell of J8 on the UIF PCB until it clicks. Insert thekeypad ribbon cable into J8 of the UIF PCB. Slide the outer shell of J8down until it clicks.

10. Connect the speaker cable to J13 of the UIF PCB.

11. Complete steps 8 through 10 of procedure in paragraph 6.10.



6-13

6.12 ALARM SPEAKER REMOVAL/INSTALLATION

Removal


2. Disconnect the speaker wire harness from J13 on the UIF PCB(see Figure 6-11).

3. Pull the retaining tab back from the speaker and lift the speaker out of thetop case.

Connect speakerwires to J13 connector

Figure 6-11: Alarm Speaker

Installation

4. Pull the retaining tab back and insert the speaker into the top case.

5. Connect speaker wire harness to J13 on the UIF PCB.


7-1

SECTION 7: SPARE PARTS7.1 Introduction

7.1 INTRODUCTION

Spare parts, along with part numbers, are shown in Table 7-1. Item numberscorrespond to the callout numbers in Figure 7-1.

Table 7-1: Parts List

Item Description Part No.1 Top Case Assembly (Membrane Panel Included) 0484512 Fuse Drawer 6915003 Fuses 6910324 Power Entry Module 6914995 Cooling Fan 0354696 Power Supply 0352007 LCD PCB 0354038 Battery 6401199 Battery Bracket 03530710 UIF PCB 035263

Sensor Lock (not shown) 022943Alarm Speaker (not shown) 033494Ground Clip (not shown) 035400Rubber Feet (not shown) 4-003818-00Power Cord (not shown) U.S. 071505

International 901862U.K. 901863

Section 7: Spare Parts

7-2

Figure 7-1 shows the NPB-195 expanded view with numbers relating to the spareparts list.

NPB-195

10

4

7

8

1

5

9

2

3

6

Figure 7-1: NPB-195 Expanded View

8-1

SECTION 8: PACKING FOR SHIPMENT8.1 General Instructions8.2 Repacking in Original Carton8.3 Repacking in a Different Carton

To ship the monitor for any reason, follow the instructions in this section.

8.1 GENERAL INSTRUCTIONS

Pack the monitor carefully. Failure to follow the instructions in this section mayresult in loss or damage not covered by any applicable Mallinckrodt warranty. Ifthe original shipping carton is not available, use another suitable carton; NorthAmerican customers may call Mallinckrodt's Technical Services Department toobtain a shipping carton.

Prior to shipping the monitor, contact your supplier or the Mallinckrodt'sTechnical Services Department for a returned goods authorization (RGA)number. Mark the shipping carton and any shipping documents with thereturned goods authorization number.

Section 8: Packing for Shipment

8-2

8.2 REPACKING IN ORIGINAL CARTON

If available, use the original carton and packing materials. Pack the monitor asfollows:

1. Place the monitor and, if necessary, accessory items in original packaging.

Figure 8-1: Repacking the NPB-195

2. Place in shipping carton and seal carton with packing tape.

3. Label carton with shipping address, return address and RGA number, ifapplicable.

Section 8: Packing for Shipment

8-3

8.3 REPACKING IN A DIFFERENT CARTON

If the original carton is not available, use the following procedure to pack theNPB-195:

1. Place the monitor in a plastic bag.

2. Locate a corrugated cardboard shipping carton with at least 200 pounds persquare inch (psi) bursting strength.

3. Fill the bottom of the carton with at least 2 inches of packing material.

4. Place the bagged unit on the layer of packing material and fill the boxcompletely with packing material.

5. Seal the carton with packing tape.

6. Label the carton with the shipping address, return address, and RGAnumber, if applicable.

9-1

SECTION 9: SPECIFICATIONS9.1 General9.2 Electrical9.3 Physical Characteristics9.4 Environmental9.5 Alarms9.6 Factory Default Settings9.7 Performance

9.1 GENERAL

Designed to meet safety requirements of:

UL 2601-1 CSA-C22.2 No. 601-1-M90, IEC 601-1 (Class I, type BF), ISO 9919,EMC per EN 60601-1-2.

9.2 ELECTRICAL

9.2.1 Protection Class

Class I: per I.E.C. 601-1, clause 2.2.4

9.2.2 Degree of Protection

Type BF: per I.E.C. 601-1, clause 2.2.26

9.2.3 Mode of Operation

Continuous

9.2.4 Battery

Type: Rechargeable sealed lead-acid, internal

Operating time: 6 hours minimum on new, fully charged battery with no backlight or alarms

Recharge period: 14 hours for full charge (in standby)

18 hours for full charge (in use)

9.2.5 Fuses

2 each 5 x 20 mm

0.5 Amp 250 volts

9.2.6 AC Power

Selectable by switch 100-120 VAC 50/60 Hz or

200-240 VAC 50/60 Hz

Section 9: Specifications

9-2

9.3 PHYSICAL CHARACTERISTICS

9.3.1 Dimensions

3.3 in. H x 10.4 in. W x 6.8 in. D

8.4 cm H x 26.4 cm W x 17.3 cm D

9.3.2 Weight

5.7 lbs

2.6 kg

9.4 ENVIRONMENTAL

9.4.1 Operating Temperature

5°C to 40°C (+41°F to +104°F)

9.4.2 Storage Temperature

-20°C to +70°C (-4°F to +158°F)

9.4.3 Operating Altitude

-390 m to +3,048 m (-1,280 ft. to +10,000 ft.)

9.4.4 Relative Humidity

15% RH to 95% RH, noncondensing

9.5 ALARMS

9.5.1 Alarm Limit Range

% Saturation: 20–100%

Pulse: 30–250 bpm

Section 9: Specifications

9-3

9.6 FACTORY DEFAULT SETTINGS

Table 9-1: Default Settings

Parameter Default ValueSpO2 High 100%SpO2 Low 85%Pulse Rate High 170 bpmPulse Rate Low 40 bpmAlarm Volume Level 5Alarm Silence Duration 60 secondsAlarm Silence Restriction Off with reminderPulse Beep Volume Level 4Baud Rate 9600Display PlethTrend SaturationContrast Mid-rangeLanguage English

9.7 PERFORMANCE

9.7.1 Measurement Range

SpO2: 0–100%

Pulse/Heart Rate: 30–250 bpm

9.7.2 Accuracy1

9.7.2.1 SpO2

Adult: 70–100% ± 2 digits

0–69% unspecified

Neonatal: 70–100% ± 3 digits

0–69% unspecified

9.7.2.2 Pulse Rate (optically derived)2

20–250 bpm ± 3 bpm

1 Accuracies are expressed as plus or minus “X” digits (saturation percentage points) betweensaturations of 70-100%. This variation equals plus or minus one standard deviation (1 SD), whichencompasses 68% of the population. All accuracy specifications are based on testing the subjectmonitor on healthy adult volunteers in induced hypoxia studies across the specified range. Adultaccuracy is determined with Oxisensor II D-25 sensors. Neonatal accuracy is determined withOxisensor II N-25 sensors.2 Accuracies are expressed as plus or minus “X” bpm across the display range. This variationequals plus or minus 1 Standard Deviation, which encompasses 68% of the population.

10-1

SECTION 10: SERIAL PORT INTERFACE PROTOCOL10-1 Introduction10-2 Enabling the Serial Port10-3 Connecting to the Serial Port10-4 Real-Time Printout10-5 Trend Data Printout10-6 Nurse Call

10.1 INTRODUCTION

When a printer is connected to the serial port on the back of the NPB-195, a real-time printout can be obtained. A new line of data is printed every 2 seconds.Column headings will be printed after every 25 lines or if one of the values in thecolumn heading changes. Changing an alarm limit, for example, would cause anew column heading to be printed. Printouts include patient and device data. Areal-time printout cannot be obtained if the unit is operating on battery power.The real-time printout is discussed in more detail in paragraph 10.4.

10.2 ENABLING THE SERIAL PORT

Real-Time data is constantly being sent to the serial port of the NPB-195. Toreceive a real-time printout, see paragraph 10.3, for instructions to make theconnection.

The baud rate may need to be changed to match the abilities of the attachedequipment. To change the baud rate, press the Setup softkey, then the Commsoftkey. Use the Adjust Up/Down buttons to select a baud rate of 2400, 9600, or19200.

10.3 CONNECTING TO THE SERIAL PORT

Data is transmitted in the standard RS-232 format. Only three lines are used:GND is the ground, TxD represents the Transmit Data Line, and RxD is theReceive Data Line. No hardware flow control is used. However, XON/XOFFflow control is supported. Pin-outs for the serial port are listed in the chartbelow.

Table 10-1: Serial Port Pin-Outs

Pin Line2 RxD3 TxD5, 10 GND11 Nurse call1, 4, 6-9, 12-15 No Connection

The pin layouts are illustrated in Figure 10-1. The conductive shell is used asearth ground. An AMP connector is used to connect to the serial port. UseAMP connector (AMP p/n 747538-1), ferrule (AMP p/n 1-747579-2), andcompatible pins (AMP p/n 66570-2).

Section 10: Serial Port Interface Protocol

10-2

9 10 11 12 13 14 15

1 2 3 4 5 6 7 8

Figure 10-1: Serial Port Pin Layout

The serial cable can be a maximum of 25 feet and must be shielded. Connectorsat both ends of the serial cable must have the shield terminated to the full 360degrees of the connector’s metal shell. If sharp bends in the cable or roughhandling is anticipated, use a braided shield.

10.4 REAL-TIME PRINTOUT

When a Real-Time display or printout is being transmitted to a printer or PC, anew line of data is printed every 2 seconds. Every 25th line is a ColumnHeading line. A column heading line is also printed any time a value in thecolumn heading line is changed. A real-time printout is shown below in Figure10-2.

Note: If the serial output stops transmitting, turn the power off and back onagain or, if connected to a PC, send an XON (Ctrl-9) to reset themonitor.

NPB-195 VERSION 1.0.0.1 CRC: XXXX SpO2 Limit: 30-100% PR Limit: 100-180 bpmTIME %SpO2 BPM PA Status01-Jul-97 14:00:00 100 120 22001-Jul-97 14:00:02 100 124 22001-Jul-97 14:00:04 100 190 22001-Jul-97 14:00:06 100 190* 220 PH01-Jul-97 14:00:08 100 190* 220 PH01-Jul-97 14:00:10 100 190* 220 PH01-Jul-97 14:00:12 100 190* 220 PH01-Jul-97 14:00:14 100 190* 220 PH01-Jul-97 14:00:16 100 190* 220 PH LB01-Jul-97 14:00:18 100 190* 220 PH LB01-Jul-97 14:00:20 100 190* 220 PH LB01-Jul-97 14:00:22 - - - - - - - - - SD LB01-Jul-97 14:00:24 - - - - - - - - - SD LB01-Jul-97 14:00:26 - - - - - - - - - SD01-Jul-97 14:00:28 - - - - - - - - - SD01-Jul-97 14:00:30 - - - - - - - - - SD01-Jul-97 14:00:32 - - - - - - - - - SD01-Jul-97 14:00:34 - - - - - - - - - PS01-Jul-97 14:00:36 - - - - - - - - - PS01-Jul-97 14:00:38 - - - - - - - - - PS01-Jul-97 14:00:40 - - - - - - - - - PS01-Jul-97 14:00:42 - - - - - - - - - PS01-Jul-97 14:00:44 - - - - - - - - - PSNPB-195 VERSION 1.0.0.1 CRC: XXXX SpO2 Limit: 30-100% PR Limit: 100-180 bpmTIME %SpO2 BPM PA Status01-Jul-97 14:00:46 - - - - - - - - - PSNPB-195 VERSION 1.0.0.1 CRC: XXXX SpO2 Limit: 80-100% PR Limit: 100-180 bpmTIME %SpO2 BPM PA Status01-Jul-97 14:00:48 79* 59* 220 SL PL LB01-Jul-97 14:00:50 79* 59* - - - PS SL PL LB

Figure 10-2: Real-Time Printout


10-3

10.4.1 Column Heading

To explain the printout it will be necessary to break it down to its keycomponents. The first two lines of the chart are the Column Heading shownbelow. Every 25th line is a Column Heading. A column heading is also printedwhenever a value of the Column Heading is changed. There are three ColumnHeading lines shown in Figure 10-2. Using the top row as the starting point,there are 25 lines before the second Column Heading is printed. The thirdColumn Heading was printed because the SpO2 limits changed from 30-100% to80-100%.NPB-195 VERSION 1.0.0.1 CRC: XXXX SpO2 Limit: 30-100% PR Limit: 100-180 bpmTIME %SpO2 BPM PA Status

10.4.1.1 Data SourceNPB-195 VERSION 1.0.0.1 CRC XXXX SpO2 Limit: 30-100% PR Limit: 100-180 bpmTIME %SpO2 BPM PA Status

Data in the highlighted box above represents the source of the printout ordisplay, in this case the NPB-195.

10.4.1.2 Software Revision LevelNPB-195 VERSION 1.0.0.1 CRC: XXXX SpO2 Limit: 30-100% PR Limit: 100-180 bpmTIME %SpO2 BPM PA Status

The next data field tells the user the software level (Version 1.0.0) and asoftware verification number (CRC XXXX). Neither of these numbers shouldchange during normal operation. The numbers will change if the monitor isserviced and receives a software upgrade.

10.4.1.3 Alarm LimitsNPB-195 VERSION 1.0.0.1 CRC: XXXX SpO2 Limit: 30-100% PR Limit: 100-180 bpmTIME %SpO2 BPM PA Status

The last data field in the top line indicates the high and the low alarm limits for%SpO2 and for the pulse rate (PR). In the example above, the low alarm limitfor SpO2 is 30% and the high alarm limit is 100%. Pulse Rate alarm limits arelow 100 bpm, and high 180 bpm.

10.4.1.4 Column HeadingsNPB-195 VERSION 1.0.0.1 CRC: XXXX SpO2 Limit: 30-100% PR Limit: 100-180 bpmTIME %SpO2 BPM PA Status

Actual column headings are in the second row of the Column Heading line.Patient data that is presented in the chart, from left to right, is the time that theline was obtained, the current %SpO2 value being measured, the current PulseRate in beats per minute (bpm), the current Pulse Amplitude (PA), and theoperating status of the NPB-195.

10.4.2 Patient Data and Operating Status

10.4.2.1 TimeTIME %SpO2 BPM PA Status01-Jul-97 14:00:00 100 120 220

The Time column represents the NPB-195 real-time clock.


10-4

10.4.2.2 Patient DataNPB-195 VERSION 1.0.0.1 CRC: XXXX SpO2 Limit: 30-100% PR Limit: 100-180 bpmTIME %SpO2 BPM PA Status01-Jul-97 14:00:06 100 190* 220 PH

Patient data and the operating status of the unit are highlighted in the displayabove. Parameter values are displayed directly beneath the heading for eachparameter. In this example the %SpO2 is 100, and the pulse rate PR is 190 beatsper minute. The “*” next to the 190 indicates that 190 beats per minute isoutside of the alarm limits, indicated in the top row, for pulse rate. If no data fora parameter is available, three dashes (- - -) will be displayed in the printout.

PA is an indication of pulse amplitude. The number can range from 0 to 254.There are no alarm parameters for this value. It can be used for trendinginformation. It is an indication of a change in pulse volume, pulse strength orcirculation.

10.4.2.3 StatusNPB-195 VERSION 1.0.0.1 CRC: XXXX SpO2 Limit: 30-100% PR Limit: 100-180 bpmTIME %SpO2 BPM PA Status01-Jul-97 14:00:06 100 190* 220 PH

The Status column indicates alarm conditions and operating status of theNPB-195. In this example the PH means Pulse High. A complete listing of thestatus codes is listed in Table 10-2. As many as 4 codes can be displayed at onetime in the Status column.

Table 10-2: Status Codes

Code Meaning

BU Battery in Use

LB Low Battery

AS Alarm Silence

AO Alarm Off

SD Sensor Disconnect

PS Pulse Search

LP Loss of Pulse

SH Sat High Limit Alarm

SL Sat Low Limit Alarm

PH Pulse Rate High Limit Alarm

PL Pulse Rate Low Limit Alarm

- - - No Data Available

* Alarm Parameter Being Violated

Note: A Sensor Disconnect will also cause three dashes (- - -) to be displayedin the patient data section of the printout.


10-5

10.5 TREND DATA PRINTOUT

The format of data displayed when a trend printout is requested is similar to thatof the real-time data. The only differences are that “TREND” is displayed in thetop row instead of the “CRC:XXXX” software verification number, and there isno “Status” column.

Readings are displayed in 5-second intervals. The values on each row are anaverage for the 5-second period.

At the end of the printout, an “Output Complete” line indicates that thetransmission was successful. If the “Outlet Complete” line is not present, ignorethe data.NPB-195 VERSION 1.0.0.1 CRC: XXXX SpO2 Limit: 30-100% PR Limit: 100-180 bpmTIME %SpO2 PR (bpm) PA22-Nov-97 14:00:05 100 120 15022-Nov-97 14:00:10 100 121 15422-Nov-97 14:00:15 100 120 150Output Complete

Figure 10-3: Trend Data Printout

10.6 NURSE CALL

A nurse call signal can be obtained by connecting to the serial port. Thisfunction is available only when the instrument is operating on AC power. Nursecall will be disabled when the unit is operating on battery power.

The remote location will be signaled anytime there is an audible alarm. If theaudible alarm has been turned off, or silenced, the nurse call function is alsoturned off.

Pin 11 on the serial port is the nurse call signal and pin 10 is ground (see Figure10-1). When there is no alarm condition, the voltage between pins 10 and 11will be -5 to -12 VDC. Whenever the monitor is in an alarm condition, theoutput between pins 10 and 11 will be +5 to +12 VDC.

11-1

SECTION 11: TECHNICAL SUPPLEMENT11-1 Introduction11-2 Oximetry Overview11-3 Circuit Analysis11-4 Functional Overview11-5 AC Input11-6 Power Supply Theory of Operation11-7 Battery11-8 User Interface PCB (UIF)11-9 Front Panel Display PCB and Controls11-10 Schematic Diagrams

11.1 INTRODUCTION

This Technical Supplement provides the reader with a discussion of oximetryprinciples and a more in-depth discussion of NPB-195 circuits. Block andschematic diagrams support a functional overview and detailed circuit analysis.The schematic diagrams are located at the end of this supplement.

11.2 OXIMETRY OVERVIEW

The NPB-195 is based on the principles of spectrophotometry and opticalplethysmography. Optical plethysmography uses light absorption technology toreproduce waveforms produced by pulsatile blood. The changes that occur inthe absorption of light due to vascular bed changes are reproduced by the pulseoximeter as plethysmographic wave forms.

Spectrophotometry uses various wavelengths of light to qualitatively measurelight absorption through given substances. Many times each second, the NPB-195 passes red and infrared light into the sensor site and determines absorption.The measurements that are taken during the arterial pulse, reflect absorption byarterial blood, nonpulsatile blood, and tissue. The measurements that areobtained between arterial pulses reflect absorption by nonpulsatile blood andtissue.

By correcting "during pulse" absorption for "between pulse" absorption, theNPB-195 determines red and infrared absorption by pulsatile arterial blood.Because oxyhemoglobin and deoxyhemoglobin differ in red and infraredabsorption, this corrected measurement can be used to determine the percent ofoxyhemoglobin in arterial blood: SpO2 is the ratio of corrected absorption ateach wavelength.

11.2.1 Functional Versus Fractional Saturation

The NPB-195 measures functional saturation, that is, oxygenated hemoglobinexpressed as a percentage of the hemoglobin that is capable of transportingoxygen. It does not detect significant levels of dyshemoglobins. In contrast,some instruments such as the IL282 Co-oximeter measure fractional saturation,that is, oxygenated hemoglobin expressed as a percentage of all measuredhemoglobin, including dyshemoglobins.

Section 11: Technical Supplement

11-2

Consequently, before comparing NPB-195 measurements with those obtained byan instrument that measures fractional saturation, measurements must beconverted as follows:

functional saturation =

fractional saturation x

100100-(% carboxyhemoglobin +%methemoglobin)

11.2.2 Measured Versus Calculated Saturation

When saturation is calculated from a blood gas measurement of the partialpressure of arterial oxygen (PaO2), the calculated value may differ from theNPB-195 SpO2 measurement. This is because the calculated saturation may nothave been corrected for the effects of variables that can shift the relationshipbetween PaO2 and saturation.

Figure 11-1 illustrates the effect that variations in pH, temperature, partialpressure of carbon dioxide (PCO2), and concentrations of 2,3-DPG and fetalhemoglobin may have on the oxyhemoglobin dissociation curve.

0

10050

Saturation(%)

pHTemperaturePCO22,3-DPG

PO2 (mmHg)

100

50

pHTemperaturePCO22,3-DPG

Fetal Hb

Figure 11-1: Oxyhemoglobin Dissociation Curve

11.3 CIRCUIT ANALYSIS

The following paragraphs discuss the operation of each of the printed circuitboards within the NPB-195 pulse oximeter. (Refer to the appropriate schematicdiagram at the end of this supplement, as necessary.)

11.4 FUNCTIONAL OVERVIEW

The functional block diagram for the NPB-195 monitor is shown in Figure 11-2.Most of the functions of the NPB-195 are performed on the UIF PCB. Functionson the UIF PCB include the SpO2 module, 331 and 196 CPUs, and Memory.Other key components of the NPB-195 are the Power Entry Module (PEM),Power Supply, and the LCD Display.


11-3

The Display module includes the Membrane Panel and the LCD Display. TheMembrane panel contains enunciators and push buttons, allowing the user toaccess information and to select various available parameters. The LCD DisplayPCB contains the LCD that presents the patient data.

SpO2 Module

MC68331CPU

Power SupplyMembrane

Panel

LCD Display

Serial port

Alarm Speaker

BatteryCharger

DCSupply

UIF PCB

PowerEntryModule

Fuses

PatientConnection

Flash ROM64K

System RAM32K

RTC

Battery

80196CPU

ROM

RAM

Figure 11-2: NPB-195 Functional Block Diagram

11.5 AC INPUT

A selector switch on the back of the NPB-195 allows the user to connect themonitor to AC power ranging from 100 VAC to 240 VAC. The switch has twopositions, one for 100 VAC through 120 VAC and one for 210 VAC through 240VAC. Verify that the switch selection matches the AC power at your locationbefore plugging the monitor into an AC outlet.

AC power enters the NPB-195 through the Power Entry Module (PEM). A 0.5-amp fuse is placed in both the “Hot” and “Neutral” lines. These user accessiblefuses are located in a fuse drawer, which is part of the PEM on the back of theinstrument.

11.6 POWER SUPPLY PCB THEORY OF OPERATION

The NPB-195 uses an unregulated linear power supply. This power supplyprovides the DC power needed to charge the battery, run the cooling fan and topower the User Interface PCB (UIF). Electro Static Discharge (ESD) protectionis also provided by the power supply.

AC power from the PEM is passed through a step-down transformer, T2, whichhas two primary and two secondary windings. If switch SW1 on the back of themonitor is in the 120 VAC position, the primary windings are in parallel. Theprimary windings are in series if SW1 is in the 240 VAC position.

Each secondary winding is fused with a 2.0 amp fuse (F1 and F2). If a shortcircuit should occur in the DC circuitry, these fuses prevent the transformer fromoverheating. The output of the transformer varies, depending on load and input.Voltage measured between the outlet of a secondary winding and ground can befrom 6 to 20 VAC. C6 and C8 filter high frequency noise from the AC line andfrom the UIF PCB before passing through the bridge rectifier.


11-4

Two outputs from the bridge rectifier are used in the NPB-195. The fan controlcircuit uses the negative output. The positive output is the Main DC rangingfrom 7 to 18 VDC. This positive voltage is used for the battery circuit and topower the UIF PCB.

11.6.1 Fan Control

A fan control circuit on the Power Supply PCB is used to control the temperatureinside the case of the NPB-195. The temperature sensor used in this circuit isU3. U3 turns on the cooling fan if the temperature inside the case gets aboveapproximately 31° C. The cooling fan runs on approximately 15 VDC.

Note: The fan is disabled if the unit is running on battery power.

11.6.2 Battery Circuits

Two circuits are included in this section of the Power Supply PCB. One circuitis used to charge the battery and the other circuit provides battery protection.

11.6.2.1 Charging Circuit

The power supply will charge the battery any time the NPB-195 is connected toAC power even if the monitor is not turned on. The voltage applied to thebattery is 6.8 ± 0.15 VDC and is current limited to 400 ± 80 mA.

Battery voltage is checked periodically by the processor. A signal from theprocessor turns the charging circuit off to allow this measurement to be taken. Ifthe processor determines the battery voltage is below 5.85 ± 0.1 VDC, a lowbattery alarm is declared.

11.6.2.2 Battery Protection

Two types of battery protection are provided by the power supply: protection forthe battery and protection from the battery.

SW2 is a resettable component that protects the battery. SW2 opens and turnsthe charging circuit off if the temperature of the battery rises above 50° C. If theoutput of the battery exceeds 2.0 amps, F3 opens. F3 protects the battery from ashort to ground of the battery output.

Protection from the battery is provided in the event of the battery beingconnected backwards. Components on the UIF PCB and the Power Supply blockand limit the voltage, to provide protection to circuits in the instrument.

11.7 BATTERY

A lead-acid battery is used in the NPB-195. It is rated at 6 VDC 4 amp-hours.When new and fully charged, the battery will operate the monitor for 6 hourswith no backlight or alarms. The battery can withstand 400 charge/dischargecycles. Recharging the battery to full capacity will take 14 hours in standby or18 hours if the instrument is being used.

Changeover from AC to battery power will not interrupt the normal monitoringoperation of the NPB-195. However, when the unit is running on battery power,the cooling fan, serial port, nurse call, and LCD backlight will be turned off.


11-5

The 331 CPU on the UIF PCB monitors the charge level of the battery. If thevoltage of the battery falls below 5.85 ± 0.1 VDC, a low battery alarm isdeclared. The instrument will continue monitoring and alarming for 15 minutesthen power down. This 15-minute alarm and power-down sequence can berepeated by turning the unit back on, provided the battery voltage remains abovethe critical level.

Battery voltage is considered critical when it decreases to 5.67 ± 0.1 DCV. If theinstrument is turned on and battery voltage is at the critical level, an error code isdisplayed and the instrument will not monitor the patient. The instrument willrun for 15 minutes with the error code displayed and then power down.

Both conditions can be corrected by plugging the unit into an AC source for 14hours to allow the battery to fully recharge.

11.8 USER INTERFACE PCB (UIF)

The UIF PCB is the heart of the NPB-195. All functions except the unregulatedDC power supply, LCD display and membrane keypad reside on the UIF PCB.

11.8.1 Regulated DC Power Supply

The UIF PCB receives the Main_DC unregulated voltage of 7 to 18 VDC fromthe Power Supply or 5.8 to 6.5 VDC from the internal battery. From either ofthese signals, the regulated power supply on the UIF PCB generates +10.0,-10.0, -5.0 and +5.0 VDC.

11.8.2 Controlling Hardware

Two microprocessors reside on the UIF PCB. The CPU is an MC68331CF(331). The CPU controls the second microprocessor, an Intel 80C196KC (196).

11.8.2.1 CPU

The 331 is the main controller of the NPB-195. The 331 controls the front paneldisplay, data storage, instrument status, serial port communication, and nursecall. The 331 monitors all buttons on the user interface.

The user interface includes the front panel display and the keypad. By pressingany of the keys on the keypad, the operator can access different functions of theNPB-195. The 331 will recognize the keystroke and make the appropriatechange to the monitor. Some of the changes operators can make include theview on the LCD display, alarm limits, and alarm volume. SECTION 4: of thismanual goes into more detail about the use of the softkeys.

Patient data is stored by the NPB-195 and can be downloaded to a printerthrough the serial port provided on the back of the instrument. An in-depthdiscussion of the serial port is covered in the Section 10 of this manual.

Power to the NPB-195 is monitored by the 331, which will determine if theinstrument is running on AC, or on battery power. If the monitor is running onAC power, the 331 will periodically turn off the battery charge circuit to checkthe battery charge level.


11-6

When the 331 sends a signal to the alarm speaker, three items are used todetermine the tone that is sent. First, pulse tones change with the %SpO2 valuebeing measured. The pulse beep tone will rise and fall with the measured%SpO2. Second, three levels of alarms, each with its own tone, can occur: High,Medium and Low priority. Third, the volume of the alarm is user adjustable.Alarm volume can be adjusted from 1 to level 10, with level 10 being the highestvolume.

When AC powers the NPB-195, the nurse call function is available. If noaudible alarms are occurring, the output from the serial port (- pin 10, + pin 11)will be from minus 3 to minus 10 VDC. When there is an audible alarm (notsilenced or disabled) the output will be positive 3 to positive 10 VDC.

11.8.2.2 196

Primary responsibilities of the 196 include controlling the SpO2 function andcommunicating data to the 331.

A pulse width modulator (PWM) function built into the 196 controls the SpO2function. PWM signals are sent to control the intensity of the LEDs in thesensor. The gain of amplifiers receiving return signals from the photodetector inthe sensor are also controlled by PWM signals.

Analog signals are received from the SpO2 circuit on the UIF PCB. An Analogto Digital (A/D) function in the 196 converts these signals to the digital valuesfor %SpO2 and heart rate. These values are then sent to the 331 to be displayedand stored.

11.8.3 Sensor Output/LED Control

The SpO2 analog circuitry provides control of the red and IR LEDs such that thereceived signals are within the dynamic range of the input amplifier. Becauseexcessive current to the LEDs will induce changes in their spectral output, it issometimes necessary to increase the received signal channel gain. To that point,the CPU controls both the current to the LEDs and the amplification in the signalchannel.

At initialization of transmission, the LEDs' intensity level is based on previousrunning conditions, and the transmission intensity is adjusted until the receivedsignals match the range of the A/D converter. If the LEDs reach maximumoutput without the necessary signal strength, the PWMs will increase the channelgain. The PWM lines will select either a change in the LED current or signalgain, but will not do both simultaneously.

The LED drive circuit switches between red and IR transmission and disablesboth for a time between transmissions in order to provide a no-transmissionreference. To prevent excessive heat build-up and prolong battery life, eachLED is on for only a small portion of the duty cycle. Also, the frequency ofswitching is well above that of motion artifact and not a harmonic of known ACtransmissions. The LED switching frequency is 1.485 kHz. The IR transmissionalone, and the red transmission alone, will each be on for about one-fifth of theduty cycle; this cycle is controlled by the 196.


11-7

11.8.4 Input Conditioning

Input to the SpO2 analog circuit is the current output of the sensor photodiode.In order to condition the signal current, it is necessary to convert the current tovoltage.

Because the IR and red signals are absorbed differently by body tissue, theirreceived signal intensities are at different levels. Therefore, the IR and redsignals must be demodulated and then amplified separately in order to comparethem to each other. De-multiplexing is accomplished by means of two circuitsthat alternately select the IR and red signal. Two switches that are coordinatedwith the IR and red transmissions control selection of the circuits. A filter with alarge time-constant follows to smooth the signal and remove noise beforeamplification.

11.8.5 Signal Gain

The separated IR and red signals are amplified so that their DC values are withinthe range of the A/D converter. Because the received IR and red signals aretypically at different current levels, the signal gain circuits provide independentamplification for each signal as needed. The gain in these circuits is adjusted bymeans of the PWM lines from the CPU.

After the IR and red signals are amplified, they are filtered to improve thesignal-to-noise ratio and clamped to a reference voltage to prevent the combinedAC and DC signal from exceeding an acceptable input voltage from the A/Dconverter.

11.8.6 Variable Gain Circuits

The two variable gain circuits are functionally equivalent. The gain of eachcircuit is contingent upon the signal’s received level and is controlled to bringeach signal to approximately 3.5 V. Each circuit uses an amplifier and oneswitch in the triple SPDT analog-multiplexing unit.

11.8.7 AC Ranging

In order to achieve a specified level of oxygen saturation measurement and tostill use a standard-type combined CPU and A/D converter, the DC offset issubtracted from each signal. The DC offsets are subtracted by using an analogswitch to set the mean signal value to the mean of the range of the A/D converterwhenever necessary. The AC modulation is then superimposed upon that DClevel. This is also known as AC ranging.

Each AC signal is subsequently amplified such that its peak-to-peak values spanone-fifth of the range of the A/D converter. The amplified AC signals are thenfiltered to remove the residual effects of the PWM modulations and, finally, areinput to the CPU. The combined AC and DC signals for both IR and red signalsare separately input to the A/D converter.

11.8.8 Real-Time Clock (RTC)

Real time is tracked by the NPB-195. As long as battery power or AC power isavailable, the instrument will keep time. If the battery is removed, the time clockwill have to be reset.


11-8

The LCD will display real time when trends are selected. A time stamp isprinted for each line of data on a printout. Real-time data is displayed andprinted as Day, Month, Year, Hours, Minutes, and Seconds.

11.8.9 Patient Data Storage

Patient data is stored once every 5 seconds. A maximum of 24 hours of patientdata can be stored. Up to 50 alarm limit changes can be retained. Trend datawill be retained for a minimum of 30 days.

If battery power is disconnected or depleted, patient data will be lost. Data isstored with error detection coding. If data stored in memory is corrupted, it isdiscarded.

11.9 FRONT PANEL DISPLAY PCB AND CONTROLS

11.9.1 Display PCB

The Front Panel LCD display PCB displays patient data and status of themonitor.

At power up, all indicators and pixels are illuminated to allow verification oftheir proper operation. Next, the NPB logo and the software revision level aredisplayed. After this cycle has been completed the instrument is ready to beginmonitoring.

The LCD allows the user to select among several different types of displays.Graphs, which are used for trend screens, can be displayed. Real-time patientdata can include a plethysmographic waveform and digital values for SpO2 andBPM. If a plethysmograph is not desired, the operator can select to view onlydigital data for SpO2 and BPM along with a blip bar to show pulse intensity.

11.9.2 Membrane Keypad

A membrane keypad is mounted as part of the top case. A ribbon cable from thekeypad passes through the top case and connects to the UIF PCB. Nine keysallow the operator to access different functions of the NPB-195.

These keys allow the user to select and adjust the alarm limits, cycle power tothe unit, and to silence the alarm. Alarm volume and alarm silence duration canalso be adjusted via the keypad. Pressing the softkeys can access a number ofother functions. These functions are discussed in greater detail in Section 4.

Four LEDs are also part of the membrane keypad. These LEDs indicate ACpower available, low battery, pulse search, and alarm silence.

11.10 SCHEMATIC DIAGRAMS

The following part locator diagrams and schematics are included in this section:

Figure 11-3: UIF PCB Front End Red/IR Schematic DiagramFigure 11-4: Front End LED Drive Schematic DiagramFigure 11-5: Front End Output Schematic DiagramFigure 11-6: Front End Power Supply Schematic DiagramFigure 11-7: Isolation Barrier EIA-232 Port Schematic Diagram


11-9

Figure 11-8: CPU Core Schematic Diagram AFigure 11-9: CPU Core Schematic Diagram BFigure 11-10: MC331 CPU Core Schematic Diagram AFigure 11-11: MC331 CPU Core Schematic Diagram BFigure 11-12: Display Driver Schematic DiagramFigure 11-13: Speaker Driver Schematic DiagramFigure 11-14: Core Power Supply Schematic DiagramFigure 11-15: Power On/Off Circuit Schematic DiagramFigure 11-16: UIF PCB Parts Locator DiagramFigure 11-17: Power Supply Schematic DiagramFigure 11-18: Power Supply Parts Locator Diagram

Figure 11-3UIF PCB Front End Schematic Diagram

FRONT END RED/IR

IR CHANNEL

AD822 BYPASS

DG201S BYPASS

RED CHANNEL

TP2

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035262

11-11

Figure 11-4Front End LED Drive Schematic Diagram

LED DRIVE

FRONT END LED DRIVE

S

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035262

11-13

Figure 11-5Front End Output Schematic Diagram

035262

DG201S BYPASS DG201S SPARES

Guard Ring

Guard Ring

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C471000P

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11-15

Figure 11-6Front End Power Supply Schematic Diagram

035262

CURRENT

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11-17

035262

clockshigh power

SH1 BD MTG HOLE

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+I192

TXDOUT

I99

I97

IGNDTP24

I87

VMINUS

VMINUS

EXCOM-SHTDWN

100M

TH

R76

1/4W

DT1600VTH

DTRLDR

TX

6N136U18

TH

7

6

8

2

3 553

2

8

6

7

DTR

CR16BAV99

21

33

BAV99CR15

21

33

CR14BAV99

21

33

22VSMCJ22CCR11

21

21

R744.02K

4.02KR73

VDD

U15

13V-

V+ 2

11T2OUT

T2DIN4

T1OUT 12

3 T1DIN

RTRI 8

R2LDR6 9R2IN

5 R1LDR

R1IN 10

ISO_GND14

7 BYP

AC1

MAX251S

1

7

14

10

596

8

3

12

4

11

2

13

1N914CR12

133 1

U164N26

45

6

12TH

451

2 6

VDD

6N136U17

TH

7

6

8

2

355 3

2

8

6

7

IBAV99CR13

21

33

U19

EN8

R1OUT9

R2OUT12

SHDN1

PWR14

D2 13

R2DIN 11R1DIN 10

GND 7

T2LDR 6T2IN5T1IN4 T1LDR 3

D1 2

MAX250S

8

912

1

1413

1110

7

654 3

2

SCHOTT 67129080T2

6

43

2

1 6

43

2

1

RXDIN

RXDLDR

NURSE-CALLTXD

RXD

TP31

TP29

I86

C721.0U20V

+

VPLUS

VPLUS

20V1.0UC73

+

I98

TP26

NCALOUT

J2

CON_DB15F

16

1

8

7

6

5

4

3

15

2

14

13

12

11

10

9

1717

9

10

11

12

13

14

2

15

3

4

5

6

7

8

1

16

RXD232

I

I88

R7210.0K

IGND

L21 600R

L22600R

L23600R

C893300P

50V

C711.0U20V

+

50V2200P

C75

C1173300P

50V

CLKDRV2

CLKDRV1

0.1U

C76Z5U

I238

I237

TXDLDR

Figure 11-7Isolation Barrier EIA-232 Port Schematic Diagram

11-19

Figure 11-8CPU Core Schematic Diagram A

035262

IS NOT AVAILABLEONLY IF ATP-SMHC49S IS USED

CPU CORE

ADDRESS LATCHING

CLINICAL SERIALDATA CONNECTOR

RAM --- E000 - FFFF

ROM --- 0000 - DFFF

ADDRESS DECODING - MEMORY MAPPING

SERIAL INTERFACE

I119

RRD-LRWR-L

I162I164

I161

I315I316

RSCI_CLK

CLK_OUT TP33

121R167

VDD

I305I304

I301

Q11

2

13

2N3904S

31

2

VDD

RAMEN-L

10MHZY2

ATP-SM

144 1

U21

74HC573S

1 OCC11

8Q 128D97Q 137D86Q 146D75Q 155D64Q 165 4D3Q 174 3D2Q 183 2D1Q 192 1D2 19

3 184 175 166 157 148 139 12

111

VDD

10V47UC116

7343

+

I163

RALE-L

I170

I107I105

U20

74HC573S

1 OCC11

8Q 128D97Q 137D86Q 146D75Q 155D64Q5 4D3Q 174 3D2Q 183 2D1Q 192 1D2

345 166789

111

I169WR-L

I167

ADDR13ADDR12ADDR11

ADDR0

I149

AD8

AD6

I126

R87 121

VREF

C820.1U

I104 I106 I101

10V47UC102

7343

+

I108

I109

RWD_RST

Y510MHZ

21

HC49S

21

VDD

121R75

C910.1U

PHOTOI

RAD8RAD9RAD10RAD11RAD12RAD13RAD14RAD15

CDRXD

REDAC

IRACRSENS

IRLED/AV

REDLED/AVZERO-L

REDDC

IRDC

22PC90

R86 121

U27

80C196KC

6 ACH0/P0.05 ACH1/P0.17 ACH2/P0.24 ACH3/P0.3

11 ACH4/P0.410 ACH5/P0.5

8 ACH6/P0.69 ACH7/P0.7

60AD059AD1

50AD1049AD1148AD1247AD13

AD14 4645AD15

58AD257AD356AD455AD554AD653AD752AD851AD9

12 ANGND

65CLKOUT

14GND136GND268GND3

24 HSI0HSI125

26HSI2/HSO427HSI3/HSO5

28HSO029HSO134HSO235HSO3

63INST

P1.01920 P1.1

P1.22122 P1.3/PWM123 P1.4/PWM2

P2.0/TXD1817 P2.1/RXD

P2.2/EXTINT1544 P2.3/T2CLK

P2.4/T2RST4239 P2.5/PWM033 P2.6/TWUP-DN

P2.7/T2CAPT38

PWR1

37 VPPVREF13

67XTAL166XTAL2

62ADV

30 BREQ31 HLDA32 HOLD

61RD

41WRH/BHE

40WRL/WR

ALE/

P1.5/P1.6/P1.7/

64 BUSWIDTH

2 EA

3 NMI

16 RESETREADY43

25

18

3833

24

43

272635342928

6423

16

32

474849

313023222120

5051525354555657585960

19

98

1011

4

657

121337

65

6667

1

683614

63

4546

4041

62

61

1715444239

U30

~RST 6

RST 5

LTC1232

VCC 8

TOL3

TD2 ST 7

PBRST1

GND4

6

5

8

3

2 7

1

4

I100

R88121

WD_RST

TP32

I92

I110

RAMEN-L AD14AD13AD12AD11AD10AD9AD8

AD15

AD7AD6AD5AD4AD3AD2AD1AD0

AD14AD13AD12AD11AD10AD9AD8AD7AD6AD5AD4AD3AD2AD1AD0

AD15

AD[15:0]

10.0KR92

ALE

VDD

RAD7RAD6RAD5RAD4RAD3RAD2RAD1RAD0

RAD15RAD7

I144I143

I142I141

I140I139I138

I137I136

I135I134

I133I132

I131I130 AD0

AD1AD2AD3AD4AD5

AD7

AD9AD10AD11AD12AD13AD14AD15I129 ADDR15

ADDR14

ADDR10ADDR9

ADDR7

ADDR5ADDR4ADDR3ADDR2ADDR1

I159I158

I157I156

I155I154

I153I152

I151I150

I148I147

I146I145

ADDR6

ADDR8

I160

RD-LALEI168

VDD

U22

74HC10S

345

6

TP28

TP27

U22

74HC10S

1213

21

I91

ROM_DIS-L

ROMEN-L

ADDR14ADDR15ADDR13

ADDR[15:0]

ADDR15ADDR14ADDR13ADDR12ADDR11ADDR10ADDR9ADDR8

ADDR6ADDR5ADDR4ADDR3ADDR2ADDR1ADDR0

ADDR7

ADDR[15:0]

ALE

J4

CON_5

5432112345

I103

I176I177I178

C810.1UZ5U

Z5U0.1UC77

C800.1UZ5U

VDD

VDD

120RP2

910111213141516

87654321

910111213141516

87654321

RP1 120

910111213141516

8765432112345678

16151413121110

9

R89221

R163221

I302

I206

I283

FERESET

TP36

RD-L

WR-L

SLAVESEL

SLAVESEL

ALE

I165

I74I89 I166

I303

R8110.0K

CDRXDCDTXD

VDD

R8010.0K

TP34RST-L

10.0KR110

VDD

I225

C9522P

R9110.0K

R82100K

L7LEDDIS

L8

L9IR/RED

RWD_RST

L11

L10PWM1

PWM2

L15

L14

CDTXD

PWM0

L16

L18

L17SAMPRED

OFF/ON

SAMPIR

221R166

SCI_CLK

50V470PC79

4700P

L6

1 2

3 443

21

VDD

196PWR

MOSI

RMOSI

11-21

035262

Figure 11-9PIC and Speaker Schematic Diagram B

STATIC RAM

EPROMU31

N195SPO2

64KX16

27C1024

2 VPP

44PWR

43 PGM

22 OE

N.C.42

12GND2GND1 34

D9 10D8 11

14D7

15D6

16D5

17D4

18D3

19D2

D15 4D14 5D13 6D12 7D11 8D10 9

20D1

21D0

3 CE

35 A9

32 A8

31 A7

30 A6

29 A5

28 A4

27 A3

26 A2

41 A15

40 A14

39 A13

38 A12

37 A11

36 A10

25 A1

24 A02425

363738394041

2627282930313235

3

2120

987654

1918171615141110

3412

42

2243

44

2

0R94

VDD

I179

10.0KR83

SRAMPWR

Z5U0.1UC86

C850.1UZ5U10V

47UC103

7343

+

U32 32KX8

A010

A19

A10A11A12A1326

1 A14

A28

A37

A46

A55

A643 A7

A8A9

CE20 14GND

O0 1112O113O215O316O417O518O619O7

OE22

28PWR

27 WE

55257S

109

261

876543

20 14

1112131516171819

22

28

27WR-L

RAMEN-L

VDD

10.0KR79

I203

I202

I193

7343

C10447U10V

+

L20

L19

VDD

ROMEN-L

AD[15:0]

AD0

AD0

AD1AD2AD3AD4AD5AD6AD7

AD9AD8AD7AD6AD5AD4AD3AD2AD1

AD15AD14AD13AD12AD11AD10

EPROMPWR

BIGROM

RD-L

RD-L

ADDR[15:0]

ADDR12ADDR11ADDR10ADDR9ADDR8ADDR7ADDR6ADDR5ADDR4ADDR3ADDR2ADDR1ADDR0

ADDR15

ADDR3

ADDR1ADDR2

ADDR10ADDR9ADDR8ADDR7ADDR6ADDR5ADDR4

ADDR14ADDR13ADDR12ADDR11

11-23

035262

Figure 11-10MC331 CPU Core Schematic Diagram A

Y3

32

.76

8K

HZ

14

EC

PS

M2

9T

41

battery backed power

From Power Supply

REAL TIME CLOCK

MC331 CPU CORE

TP30

A0A1A2A3A4A5A6A7A8

A[16:0]A16A15A14A13A12A11A10A9

RA0

C1524.7P

CR31VC1206

5.6V

12

12

47UC137

10V

+

R/WLDSACK0DSACK1

I210U45

60XTAL

64XFC

VSS96759 VSS8

VSS75140 VSS6

VSS53429 VSS4

VSS3178 VSS2

VSS15127117 VSS14

VSS13106101 VSS12

VSS119583 VSS10

VSS12

61VDDSYN

84 VDD9VDD865

63 VDD7VDD650

39 VDD5VDD428

18 VDD3VDD27

126 VDD13VDD12116

107 VDD11VDD1096

1 VDD1

52 TXD

80SIZ1

81SIZ0

45 SCK

53 RXD

79R-/W

PWMB129130 PWMA

PCLK1284 PAI

6 OC4

10 OC3OC211

12 OC1

44 MOSI

78MODCLK

43 MISO

54IPIPE-DSO55IFETCH-DSI

IC4/OC55IC313

14 IC2IC115

58FREEZE-QUOT

118FCO-/CS3

120FC2-/CS5

119FC1-/CS4

62EXTAL

99D9

100D8

102D7

103D6

104D5

105D4

108D3

109D2

91D15

92D14

93D13

94D12

97D11

98D10

110D1

111D0

66CLKOUT

A9 3027A8

A7 2625A6

A5 2423A4

A3 22

125A23-/CS10

124A22-/CS9

123A21-/CS8

122A20-/CS7

21A2

121A19-/CS6

42A18A17 41

38A16A15 37

36A14A13 35

33A12A11 32

31A10

A1 2090A0

57/TSTIME-TSC

/RMC 86

/RESET68

49 /PCS3

48 /PCS2

47 /PCS1

46 /PCS0-/SS

71 /IRQ7

72 /IRQ6

73 /IRQ5

74 /IRQ4

75 /IRQ3

76 /IRQ2

77 /IRQ1

69 /HALT

88/DSACK1/DSACK0 89

85/DS

112/CSBOOT113/BR-/CS0

56/BKPT-DSCLK

115/BGACK-/CS2

114/BG-/CS1

70 /BERR

87 /AVEC

82/AS

68331

82

87

70

114115

56

113112

85

8988

69

77767574737271

46474849

68

86

57

9020

313233353637384142121

21

122123124125

22232425262730

66

111110

989794939291

10910810510410310210099

62

119120

118

58

151413

5

5554

43

78

44

121110

6

4128

130129

79

53

45

8180

52

1

96107116126

718283950636584

61

2

8395

101106117127

817293440515967

64

60

221R153

L2

I205

L13

I235BATT_CHECK

C1290.1U0805

C1280.1U08050805

0.1UC126C123

0.1U08050805

0.1UC127C121

0.1U08050805

0.1UC120

C1240.1U08050805

0.1UC125C134

0.1U08050805

0.1UC133C135

0.1U08050805

0.1UC122

10K

RP6

1 2 3 4

8 7 6 55678

4321

I310

L3

I312

I307

I198I197

BOOTROML

RPBCSL

VDD

RESETL

R96 221

I24

2

I279

EEPENEEPCLKEEPDI

I240

I313

I228RDSPLRDL

RD0RROMLATECSL

RA1RA12 I211

I213I212RA16

R/WLR I229I227RD13I226

I230

VDD

VDD

RP16220

87654

321

DSPLRDL

RAMCSL

IPIPE0IPIPE1FREEZEBKPTL

C13822P

J15

8642

7531

CON_BDM8

1357

2468

I94

VDD

16V

C13610U

+

RP7

10K

1 2 3 4

8 7 6 55678

4321

RP11

10K

1 2 3 4

8 7 6 5

1 2 3 4

8 7 6 5

U44 8KX8

CS1

5GND

6ORG

SCLK2

SDI3

SDO 4

V+8

93C56S

8

4

32

6

5

1

VDD

10.0MR149

332KR150

I201

C1300.1UZ5U

Z5U0.1UC132

22PC140

C1410.01U

L447Z

VDD

220RP15 8

765 4

321

5678

4321

RP18220

8765 4

3211234

8765

I204

TP58

VDD

R10410.0K

VDD

10K

RP9

1 2 3 4

8 7 6 5

1 2 3 4

8 7 6 5

RP10

10K

1 2 3 4

8 7 6 5

1 2 3 4

8 7 6 5

10K

RP8

1 2 3 4

8 7 6 55678

4321

221R152

TP56

DSPLYCSL

221R105

I231

I232

I233I234

I314

I209 EEPDO

I66

I241

I239

I282

120RP12

910111213141516

87654321

910111213141516

87654321

Y132.768KHZ

14

ECPSM29T

4 1

U47TC7S00F

5

3

1

24

5

3

ROMLATECSL

VDD

I281

I102I311

I308I306

I309

I93

Z5U0.1UC139

DS1811

U46

VDD

2

RESETL 1

GND3

1

VDD

R1351.00K

Z5U0.1UC131

VDD

RESETL

U43

DS1302Z

1PWR2

GND 4

PWR1 8

7 SCLK

3 X2

6 I/ORST5

2 X12

56

3

7

8

4

1

I243

RAMPWR TP59

RTCCLKRTCDATA

RTCSEL

RTCSEL

FONTSEL I53

NURSE-CALLAC_OK-L

RTCCLK

FERESETEEPDO

VDDI

IPIPE0IPIPE1

EEPENEEPCLK

FREEZE

D15

D0

D14D13D12D11D10D9

D6D5D4D3D2D1

D8D7

D[0:15]

VDDI

RESETL

RA1RA2RA3RA4RA5RA6RA7RA8RA9RA10RA11RA12RA13RA14RA15RA16

BIULEDDRASLEDDRAC-LED

RTCSELLRROMLATECSL

R/WLR

DSLASLSIZ0SIZ1RMCL

BKPTL

RBOOTROMLRRAMCSLRDSPLCSLRDSPLRDL

PWR_BTN_RSTPWR_BTN_RSTRPBCSL

PSLEDDR

CLKOUT

VDDSYN

CTRSTINCCTRSTUPEXCOM-SHTDWNSLAVESELMOSI

SCI_CLK

TXDRXD

PWM_FREQ

FFONTSELEEPDI

RTCDATA

RTCDATA

PWM_VOL

IRQ7-LCRIT_BATT-LLOW_BATT-LBK-LT-ONBTN_PRS_L

FBATT_CHECKTURN_OFF

HALTLBERRL

VDDI

XFC

PBCSL

11-25

Figure 11-11MC331 CPU Core Schematic Diagram B

035262

11-27

U42

N195BOOT

FLASH64KX16

29C1024S

A024

A125

A1036

A1137

A1238

A1339

A1440

A1541

A226

A327

A428

A529

A630

A731

A832

A935

CE3

D021

D1 20

9D108D117D126D135D144D15

D2 19

D3 18

D4 17

D5 16

D6 15

D7 1411D810D9

12GND1GND2 34

OE22

PWR 44

WE4343

44

22

3412

1011141516171819

456789

2021

3

3532313029282726

414039383736

2524

Boot SelectJumper & Dipshunts

J14

21

J14J14

ProductionCode DebugFlash Debug

42

53

643

146

Z5U0.1UC145

D10

D4

D9D8

D11D12D13D14D15

D[15:0]D[15:0]

D[0:15]

D15D14D13D12D11D10D9D8D7D6D5

D3D2D1D0

120RP13

910111213141516

87654321

910111213141516

87654321

RD15RD14

RP14120

910111213141516

8765432112345678

161514131211109

FLASHPWR

I319I318I295

U40

74HC32S

4

56

W-RL

I278

BOOTROML A0

A4A5A6A7A8A9A10A11A12A13A14A15A16

A3A2A1

A[16:0]

A16A15A14A13A12A11A10A9A8A7A6A5A4A3A2A1

A[16:0]A[16:0]A[16:0]

I195

10.0KR148

ROMLATECSL

U22

74HC10S

81110

9

RAMCSL RAMCSL

VDD

I257 A15

R/WL R/WL

R/WL

RESETL RESETL

A0

VDD

RAMPWR

Z5U0.1UC101

10V47UC118

+

J14

CON_3X2

654321

642

531

10.0KR146

VDD

U41 128KX8

431000S

29 WE

32PWR

24 OE16GND

21D7

20D6

19D5

18D4

17D3

15D2

14D1

13D0

22 CEL30 CEH

26 A9

27 A8

5 A7

6 A6

7 A5

8 A4

9 A3

10 A2

2 A16

31 A15

3 A14

28 A13

4 A12

25 A11

23 A10

11 A1

12 A01211

2325

428

331

2

1098765

2726

3022

1314151718192021

1624

32

29

10.0KR147

VDD

C11947U10V

+

TP55

FLSHOEL

A1

I260I259I258

I256I255I254I253

I252I251I250I249

I248I247I246I245

A3A4A5A6A7A8A9A10A11A12A13A14

A2

D12D13D14

D8D9D10D11

D4D5D6D7

D2D3

I276I275I274I273

I272I271I270I269

I268I267I266I265

I262I261

D1D0

D15I263

A16I280

I264

0.95UL12

I317

EXMEMEN-L

I320I321I322

RD1RD0

RD2RD3RD4RD5RD6RD7RD8RD9RD10RD11RD12RD13

BOOTFLSHL

BOOTFLSHL

Figure 11-12Display Driver Schematic Diagram

035262

11-29

I113

Turn off control

TO DISPLAY

74HC540filter cap for

filter cap for 74HC245

MEMBRANE PANEL CONNECTOR

filter cap for 74HC32

CCFL inverter

PBCSL

CR33

VC12065.6V

12 12

SOFTKEY4

S

D[15:0]

D8D9D10D11D12D13D14D15

D[15:0]

D14D15

D13D12D11D10D9D8

AC_OK

AC_OK

AC-LED

AC-LED

ACPWRLED

74HC32SU40

12

1311

I327

U40 74HC32S

810

9

I326

121R151

U40

74HC32S

32

1

7343

C14247U10V

+

7343

C11047U10V

+

100UHL5Z5U

0.1UC97

PSLED

249R154

249R138

R137249

J9

CON_IDC20

1

1011 1213 1415 1617 1819

2

20

3 45 67 899

8765432

1917151311

1

DSPLR/WL

DSPLR/WL

RBD4

RBD3

U50

DIR

A8A7A6A5A4A3A2A1 B1

B2B3B4B5B6B7B8

G

74HC245S

2

9876543

191

1112131415161718

DSPLA0

L24

R/WL

I290

VEE

L1121R136

10.0

KR

158

ONBUTTON

ONBUTTON

J5

CON_4L_098

43211234

I323VDD

VD

D

10UC147

16V

+

Z5U0.1UC146

DSPLVDD

BK-LT-ON

BK-LT-ON

VDD

Z5U0.1UC99

I298

I300

3_3V

J8CON_FLEX16

98765432

16151413121110

11

1011 1213 1415 16

23 45 67 89

10.0KR139

100KR143

CR23

1 3

1N914S

31

CR22

1 3

1N914S

31

U48TC7S00F

5

3

42

1

Q23

3

21 2N7002S

3

21

Q222N3906S

2

31

2

31

VDD

R162

10.0

K

R161

10.0

K

10.0

KR

160

R159

10.0

K

R157

10.0

K

10.0

KR

156

I286

I288

I287

I284

HV_OUT

Q212N3906S

2

31

2

31

Q202N3906S

2

31

2

31

Q192N3906S

2

31

2

31

SOFTKEY3

ASLEDDR

BIULEDDR

PSLEDDR

SOFTKEY2SOFTKEY1BIULED

CNTRSTUPASLED

ALRMSILDOWN

PSLEDACPWRLED

A1 TH

CXA-L10

1 VDD

2 GND1

3

5GND2

44

5

3

2

1

C1000.1UZ5U

VDD

VDD

4.02KR140

R1414.02K

R1424.02K

Q12SI9953

1

78

2

I285

I289

R155

10.0

K

SOFTKEY2SOFTKEY3SOFTKEY4UPDOWNCNTRSTALRMSIL

U34

11Y8

12Y7

13Y6

14Y5

15Y4

16Y3

17Y2

18Y1

9 A8

8 A7

7 A6

6 A5

5 A4

4 A3

3 A2

2 A1

192G

11G

74HC540S

119

23456789

1817161514131211

VDD 20.0KR144

I296

I297

I299

CR25

21N4934

1

TH

2 1

CR24

21N4934

1

TH

2 1

68.1R145

8.25KR101

I221

VDD

C1060.1U

Z5U

I324

SOFTKEY1

DSPLVEE

S

121R169RBD0

RBD1R170 121

RBD2121R171

R172 121

121R173

R174 121RBD5

121R175 RBD6

121R176RBD7

BD4

BD1

BD2

BD3

BD5

BD6

BD7

BD0

BD0BD2BD4BD6

BD[7:0]

BD7BD5BD3BD1RESETL

RESETL

FONTSEL

DSPLRDL

DSPLRDL

ASLEDBIULED

CCFLPWR

121R118

A0

DSPLYCSLDSPLYCSL

CR32

VC12065.6V

122 1

I328

DSPDTACSL

DSPDTACSL

Figure 11-13Speaker Driver Schematic Diagram

035262

11-31

SPEAKER DRIVER

7343

C15147U10V

+

10V47UC150

7343

+

10V47UC149

7343

+

10V47UC148

7343

+

VDD

X9313 EPOTU24

U/

INC1

CS7 VCC

8

VL 6D2VSS

4

VW 5

VH 33

5

4

2 6

8

7

1

5.6VVC1206

CR27

122

1

Z5U0.1UC92

VDD

R98249K

R9012.1K

J13

CON_2R

2121

0.047UC87

I277

I292

VDD

Q12SI99534

6 5

3

10.0KR84

10.0KR95

I199

C961.0U

20V

+

U266GND1

7 N.C.

1 VCC

VI22

VI44VO1 5

VO2 8

TDA7052A

TH

3GND27 3

1

42

6

58

0.1UC88

6.49KR99

R10010.0K

R102100K

4.99KR93

I200

TP49U25

-

+

+

-

LT1013S

2

65

4

3

U25

-

+

+

-

LT1013S

2

67

8

1

R8518.2K

TP48

TP44

TP40

+10V+10V

-10V

-10V

RESETL

CTRSTUP

CTRSTINC

VDD

U23

TC7S00F

5

33

5

42

1

PWM_VOL

PWM_FREQ

I293

I294I196

VEE

U39

-

+

+

-

TLC27L2

4

81

3

2

1.00KR132

I95

VDD

I218

U39

-

+

+

-

TLC27L2

4

87

5

6

VDD

1.00KR133

I236

035262

Figure 11-14Core Power Supply Schematic Diagram

11-33

Critical at approx 5.68V

Low at approx 5.85V

Normally HIGH, active LOW

To Linear Power Supply

Open Collector OutputActive Low Indicator

LOW to enableVDD output

Normally HIGH, active LOW

HIGH to turn ON

CORE POWER SUPPLY

0.1UC153

R113100K

10.0KR116

100KR168

10.0MR121

10.0MR177

10.0MR124

200KR123

249KR119

200K

R107

3_3V

3_3V

TP41

TP46

10.0K

R115

20.0KR178

VDD

40.2KR120

RAMPWR

Q16 SI9

95

3

87

2

1

AC_OK

CR28

MBRS330T3

12 12

100KR114

I215

I291

R112

20.0K

MAIN_OUT

MAIN_OUT

CR17

MBRS330T3

12 12

I214U35

-

+

+

-

LM393S3

2

8

4

1

1N914SCR351

331VDD

CR34

1 3

1N914S

31

R108

6.81K

CR26VC1206

5.6V

122

1

CR21MBRS130

122

1

4.99KR128

10.0MR117

GNDVIAHG2HG1

GNDVIA

GNDTP39

U36

Requires Heatsink NPB #891196

3OUT1 IN

5

HSG1

2

CS

4

LM2940H

TH 4

1 3

2 5

3.3VTP1

50V

C113

0.1U

50V

C112

0.1U

35V1.0UC109+ C108

10U16V

+

U33LT1121CZ

OUT 1IN3

GND

2

13

2

MBRS130

CR20

122 1

TP13

I224

I222

TP43

TP42I219

TP47

I216

BATT_CHECK

CON_4L_156

J6

4321

PWR_CTRL

1N914SCR18

133 1

VDD

VDD

VDD

U35

-

+

+

-

LM393S

7

4

8

6

5

R122

150KU37LT1009S

4

5

68

R125100K

TH16V470UC107

+

332KR126

100R127

VDD

VDDTP38

I217

I220

I223

0.1U

C111

50V

Q16

SI9

95

3

4

653

35V1.0UC115+

V_REF

LOW_BATT-L

Q24

2

13

2N3904S1

3

2

U38

-

+

+

-

LM393S3

2

8

4

1

U38

-

+

+

-

LM393S5

6

8

4

7

CRIT_BATT-L

CR29

BAT54

3 13 1

AC_OK-L

BATT

MAIN_DC1

VDD

0.1UC114

035262

Figure 11-15Power On/Off Circuit Schematic Diagram

From uP

From uP

To uP

Active LOW

Active LOW

249R131

3_3V 3_3V

C1440.1UZ5U

C1430.1UZ5U

TURN_OFF

PWR_BTN_RST

CD4011BU29

7

14

12

1311

CD4011BU29

7

14

8

910

CD4011BU29 7

14

6

54

U29CD4011B

31

2

14

7

U28CD4011B

1113

12

14

7

U28CD4011B

109

8

14

7

U28CD4011B

45

6

14

7

CD4011BU28

7

14

2

13

3_3V

PWR_CTRL

3_3V

QL

3_3V 3_3V

3_3V

3_3V

3_3V

QH

BTN_PRS_L

3_3V

PWR_DLY

PWR_DLY

Z5U0.1UC93

I186

I188I190

I194

I111I182

Q14

2

13

2N3904S

31

2

Q15

2

13

2N3904S2

13

20.0KR106

TP50

100KR111

100KR129

R130100K

R165100K

C980.01U

R1641.00K

TP51

I187

TP53

I189

TP54

I191

Q13

3

21 2N7002S

3

21

20.0KR134

Q17

2

13

2N3904S

31

2

Q18

2

13

2N3904S2

13

I112

VDD

VDD

R9710.0K

10.0KR103

I174

I175

I180

I181

I183

I184

I185

10KRP5

5 4

10KRP5

7 2

ONBUTTON

RP510K

36

RP510K

18

11-35

Figure 11-16UIF PCB Parts Locator Diagram

035263

11-37

TOP SIDE BOTTOM SIDE

Figure 11-17Power Supply Schematic Diagram

035199

11-39

Battery Charge

HIGH CURRENT VIAS

ESD Protection

Power Entry

Fan Control

230V

115V

Nellcor # 891196

To Fan

Requires Heat Sink

Battery -

Main Board

Battery +

BATT_OUT

Q6

3

21 2N7002S1

2

3

TH2ASB

F3

I12

NEUTRAL

I10

MPSA56Q5

1

3

22

3

1

F2

2ASB TH

I9

I8

10.0KR14 10.0K

R3 CR7

1 3

1N914S

1 3

R1610.0K

CHG_OUT

CR6

13

1N914S

3 1

R7154K

100KR6

Q2

TH2

1

3

4

IRF9510

2

3

1

CHG_IN

R1310.0K

Q3

MPSA56

1

3

2

1

3

2

10.0KR12

U2

4LM385S

8

4

8

10.0KR11

1/2W

R101.50

TH

BATT+

TH

Q42N3904

2

1

32

1

3

MBRS330T3CR4

122

1

T2

OB24-9TH

15

1312

108

63

1

10

12

15

13

8

63

1

FAC-

FAC+

MAIN_DCMAIN_DC

AC-

AC+

0.01UC8

DT1600V TH

I3

W522GA_BLK

18GA_BRNW2

22GA_ORN

W6

W9

22GA_RED

22GA_WHT

W7

W118GA _GRN/YEL

E

BATT_CHK

FAN_CTRL

0.1UC10

100MTH

R2

1/4W

I2

TP1

1/2W

R1390K

TH

LINE

NEUT_IN

LINE_IN

EPS2PC3

SW1

TH

6

54

3 2

11

23

4 5

6

SW2MTS50BTH

NC

T1

E3490ATH

429 7

2 479

E

LM358U1

-

+

+

-

4

81

3

2

0.01UC6

J1

CON_2L

21

TP2GND

250V4700P

C2

TH

C1220P250VTH

C3

250VTH

220P

THQ12N3904

2

1

33

1

2

I1

GBU8BBR1

TH

4 1

3

2

4 1

3

2

CR522V

SMCJ22C21

21

1N4702CR1

TH15V

21

21C5

15000U35VTH

+

BATT_CHK

499R4

1.00KR8

10.0KR22

U3

TH

3 GND

1 VIN2VOUT

LM35D

31

2

1.00KR9

C9

TH

100U35V

+

CR222VSMCJ22C2

112

FAN_CTRL

10.0KR17

C4100P

C70.1U

0.1U

C11

R2010.0K

1/4W

49.9

TH

R24

TH

1.00KR5

1/2W

LM358U1

-

+

+

-6

57

8

4

R2510.0M

R2173.2K

R191.00K

10.0KR23

49.9KR15

18GA_BLUW3

W8

22GA_BLK

22GA_REDW4

I5

I6

E

I7

VREF

TH2ASB

F1I11

MAIN_DC

I4

035200

Figure 11-18Power Supply Parts Locator Diagram

11-41

"+"

"-"

"GND"

"N"

"L"

NE

LLC

OR

PU

RIT

AN

BE

NN

ET

TN

PB

-190

LP

S T

OP

SID

E

12-1

SECTION 12: INDEX

BBattery

Replacement, 2-1Battery Replacement, 6-5

CChecks

Functional, 2-1Safety, 2-1

Circuit Analysis, 11-2Cleaning, 2-1Codes, Error, 5-7

DDescription, NPB-195, 1-1Disassembly, 6-1

Alarm Speaker, 6-13Cooling Fan, 6-9Display PCB, 6-10Monitor, 6-3Power Entry Module, 6-7Power Supply, 6-8UIF PCB, 6-11

EError Codes, 5-7

FFactory Default Settings, 4-1Front Panel, 1-2Functional Checks, 2-1Fuse Replacement, 6-2

IInstallation

Alarm Speaker, 6-13Cooling Fan, 6-9Display PCB, 6-11Power Entry Module, 6-7Power Supply, 6-8UIF PCB, 6-12

INSTAT, 4-6

MMaintenance, Routine, 2-1Monaul Overview, 1-1

NNPB-195 Desciption, 1-1Nurse Call, 10-5

OOximetry Overview, 11-1

PPacking for Shipment, 8-1Parts, Spare, 7-1Performance Tests, 3-1

Alarm Limit Ranges, 3-3Alarm Silence, 3-5Alarm Volume, 3-7Alarms, 3-5Battery Charge, 3-2Battery Operation, 3-8Dynamic Operating Range, 3-7Hardware, 3-5LED Excitation, 3-8Nurse Call, 3-8Operation with a Patient, 3-9Power-On Defaults, 3-3Power-On Self-Test, 3-2Power-Up, 3-2Pulse Tone Volume, 3-7Software, 3-5Using a Pulse Oximeter Tester, 3-5

Performance Verification, 3-1Power-On Self-Test, 1-4Power-On Settings, 4-1Printout

Trend Data, 10-5Printout, Real-Time, 10-2

RReal-Time Printout, 10-2Rear Panel, 1-4Reassembly

Monitor, 6-4Repairs

Who Should Do, 5-1Replacement Level Support, 5-1Replacement Parts

Obtaining, 5-1Routine Maintenance, 2-1

SSafety Checks, 2-1Safety Tests, 3-9

Earth Leakage Current, 3-10Electrical Leakage, 3-10


12-2

Enclosure Leakage Current, 3-10Ground Integrity, 3-9Patient Applied Risk Current, 3-11Patient Isolation Risk Current, 3-12

SaturationCalculated, 11-2Fractional, 11-1Functional, 11-1Measured, 11-2

Serial PortConnecting To, 10-1Enabling, 10-1

Serial Port Interface Protocol, 10-1Service Functions, 4-2

Accessing, 4-2Softkeys

ALARMS, 4-7DOWNLD, 4-7ERRLOG, 4-5EXIT, 4-3INSTAT, 4-6NEXT, 4-3PARAM, 4-3PRINT, 4-4RESET, 4-4

SAVE, 4-4SEL, 4-7TREND, 4-5

Spare Parts, 7-1Specifications, 9-1

Default, 9-3Electrical, 9-1Environmental, 9-2General, 9-1Performance, 9-3Physical, 9-2

TTrend Data Printout, 10-5Trend Printout, 4-5Troubleshooting, 5-1

Alarms, 5-4Buttons, 5-4Display, 5-4Guide, 5-2Operational Performance, 5-5Power Problems, 5-3Serial Port, 5-6