_______________________________________________________________ Maxim Integrated Products 1
For pricing, delivery, and ordering information, please contact Maxim Direct at 1-888-629-4642, or visit Maxim’s website at www.maxim-ic.com.
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16-Channel, Linear, High-Voltage Analog Switches
19-5786; Rev 2; 1/12
Ordering Information/Selector Guide
General DescriptionThe MAX4968/MAX4968A are 16-channel, high-linearity, high-voltage, bidirectional SPST analog switches with 18I (typ) on-resistance. The devices are ideal for use in applications requiring high-voltage switching controlled by a low-voltage control signal, such as ultrasound imag-ing and printers. The MAX4968A provides integrated 40kI (typ) bleed resistors on each switch terminal to discharge capacitive loads. Using HVCMOS technol-ogy, these switches combine high-voltage bilateral MOS switches and low-power CMOS logic to provide efficient control of high-voltage analog signals.
The MAX4968 is pin-to-pin compatible with the MAX14802 and Supertex HV2601. The MAX4968A is pin-to-pin compatible with the MAX14803 and Supertex HV2701. The only difference is the VPP positive supply voltage level. The MAX4968/MAX4968A require a low +10V (typ) voltage (VPP), whereas the MAX14802/MAX14803 and HV2601/HV2701 require a high +100V supply voltage.
In a typical ultrasound application, these devices do not require a dedicated high-voltage supply that implies a sig-nificant simplification of system requirement. The negative voltage supply can be shared with the transmitter, and the positive voltage supply is typically +10V.
The devices are available in the 48-pin LQFP package and are specified over the -40NC to +85NC extended temperature range.
ApplicationsMedical Ultrasound Imaging
Nondestructive Testing (NDT)/Industrial Ultrasound Imaging
Printers
FeaturesS Latch Free
SOI HVCMOS Process Technology for High Performance and Robustness
S No Dedicated High-Voltage Supplies Required
S RON Flatness Guaranteed in Entire Input Range
S Low-Power Dissipation
S Low-Charge Injection and Voltage Spike
S 25MHz Serial Interface (+2.5V to +5V)
S 2nd Harmonic Distortion < -45dB at 2MHz ± 90V Pulse
S Low Parasitic Capacitance Guarantees High Bandwidth
S DC to 30MHz Small-Signal Analog Bandwidth (CLOAD = 200pF)
S 500kHz to 20MHz High-Signal Analog Bandwidth (CLOAD = 200pF)
S Extended Input Range Up to 210VP-P
S -80dB (typ) Off-Isolation at 5MHz (50I)
S Shunt (Bleed) Resistors on Outputs (MAX4968A Only)
S Daisy-Chainable Serial Interface
+Denotes a lead(Pb)-free/RoHS-compliant package.
PART TEMP RANGE SWITCH CHANNELS BLEED RESISTOR PIN-PACKAGE
MAX4968ECM+ -40°C to +85°C 16 No 48 LQFP
MAX4968AECM+ -40°C to +85°C 16 Yes 48 LQFP
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Stresses beyond those listed under “Absolute Maximum Ratings” may cause permanent damage to the device. These are stress ratings only, and functional operation of the device at these or any other conditions beyond those indicated in the operational sections of the specifications is not implied. Exposure to absolute maximum rating conditions for extended periods may affect device reliability.
(All voltages referenced to GND.)VDD Logic Supply Voltage Range ..........................-0.3V to +6VVPP - VNN Supply Voltage ................................................ +212VVPP Supply Voltage Range ...................................-0.3V to +12VVNN Negative Supply Voltage ............................................-200VLogic Input Voltage Range (CLK, DIN, CLR) .........-0.3V to +6VLogic Input Voltage Range
(LE) ........................-0.3V to a minimum of (VPP + 0.3V) or 6VLogic Output Voltage Range (DOUT) ...... -0.3V to (VDD + 0.3V)
Analog Signal Range (SW_) ........ (VNN - 0.3V) to (VNN + 220V)Continuous Power Dissipation (TA = +70NC)
LQFP (derate 22.7mW/NC above +70NC) .................1818mWOperating Temperature Range .......................... -40NC to +85NCStorage Temperature Range ............................ -65NC to +150NCJunction Temperature ................................................... +150NCLead Temperature (soldering, 10s) ................................+300NCSoldering Temperature (reflow) ......................................+260NC
ELECTRICAL CHARACTERISTICS(VDD = +2.37V to +5.5V, VPP = +10V Q5%, VNN = 0 to -200V, TA = TMIN to TMAX, unless otherwise noted. Typical values are VDD = +3.3V, VNN = -100V, VPP = +10V at TA = +25NC.) (Note 2)
ABSOLUTE MAXIMUM RATINGS
Note 1: Package thermal resistances were obtained using the method described in JEDEC specification JESD51-7, using a four-layer board. For detailed information on package thermal considerations, refer to www.maxim-ic.com/thermal-tutorial.
PACKAGE THERMAL CHARACTERISTICS (Note 1)LQFP
Junction-to-Ambient Thermal Resistance (qJA) ..........44°C/W Junction-to-Case Thermal Resistance (qJC) ...............10°C/W
PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS
POWER SUPPLIES
VDD Logic Supply Voltage VDD +2.37 +5.5 V
VNN Supply Voltage VNN -200 0 V
VPP Supply Voltage VPP +9.5 +10 +10.5 V
VDD Static Current IDDS 4 FA
VDD Dynamic Current IDD VDD = +5V, fCLK = 5MHz, fDIN = 2.5MHz 200 FA
VNN Static Current INNS All switches remain on or off, SW_ = GND 10 25 FA
VNN Supply Dynamic Current(All Channels Switching Simultaneously)
INNVPP = +10V, VNN = -100V,fTURN_ON/OFF = 50kHz, SW_ = GND
3.3 5 mA
VPP Supply Static Current IPPS All switches remain on or off, SW_ = GND 12 25 FA
VPP Supply Dynamic Current(All Channels Switching Simultaneously)
IPPVPP = +10V, VNN = -100V,fTURN_ON/OFF = 50kHz, SW_ = GND
4 6 mA
SWITCH CHARACTERISTICS
Analog Dynamic Signal Range VSW_ AC operation only, f > 500kHz VNNVNN +
210V
Small-Signal On-Resistance RONSVPP = +10V, VNN = -100V, VSW_ = 0V, ISW_ = 5mA
18 34 I
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ELECTRICAL CHARACTERISTICS (continued)(VDD = +2.37V to +5.5V, VPP = +10V Q5%, VNN = 0 to -200V, TA = TMIN to TMAX, unless otherwise noted. Typical values are VDD = +3.3V, VNN = -100V, VPP = +10V at TA = +25NC.) (Note 2)
PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS
Small-Signal On-Resistance Matching
DRONS VPP = +10V, VNN = -100V, ISW_ = 5mA 3 %
Small-Signal On-Resistance Flatness
RONF
AC measured, fSW_ = 0.5MHz, VSW_ = 80VP-P, RLOAD = 50I, VPP = +10V, VNN = -100V
2 %
Switch Output Bleed Resistor RINT MAX4968A only 30 40 50 kI
Switch-Off Leakage ISW_(OFF) VSW_ = 0V, switch off (MAX4968 only) 0 1 FA
Switch-Off DC Offset No load (MAX4968A only) -15 0 +15 mV
Switch-On DC Offset No load (MAX4968A only) -15 0 +15 mV
Switch Output Isolation Diode Current
300ns pulse width, 2% duty cycle 3.0 A
SWITCH DYNAMIC CHARACTERISITICS
Turn-On Time tONVSW_A = +1V, RL = 100I, VNN = -100V, from enable to VSW_B = +0.9V
2 5 Fs
Turn-Off Time tOFFVSW_A = +1V, RL = 100I, VNN = -100V, from disable to VSW_B = +0.9V
2 3.5 Fs
Maximum VSW_ Slew Rate dV/dt CL = 100pF 20 V/ns
Off-Isolation VISO f = 2MHz, RL = 50I -76 dB
Crosstalk VCT f = 5MHz, RL = 50I -76 dB
SW_ Off-Capacitance CSW_(OFF) f = 1MHz, small signal close to zero 9 pF
SW_ On-Capacitance CSW_ (ON) f = 1MHz, small signal close to zero 13 pF
Output Voltage Spike VSPK RL = 50I ±70 mV
Large-Signal Analog Bandwidth (-3dB)
fBW_LCLOAD = 200pF, 60V amplitude sinusoidal burst, 1% duty cycle
30 MHz
Small-Signal Analog Bandwidth (-3dB)
fBW_SCLOAD = 200pF, 100mV amplitude sinusoidal
50 MHz
Charge Injection Q VPP = +10V, VNN = -100V, Figure 1 150 pC
LOGIC LEVELS
Logic-Input Low Voltage VIL 0.75 V
Logic-Input High Voltage VIHVDD - 0.75
V
Logic-Output Low Voltage VOL ISINK = 1mA 0.4 V
Logic-Output High Voltage VOH ISOURCE = 1mAVDD -
0.4V
Logic-Input Capacitance CIN 5 pF
Logic-Input Leakage IIN -1 +1 FA
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ELECTRICAL CHARACTERISTICS (continued)(VDD = +2.37V to +5.5V, VPP = +10V Q5%, VNN = 0 to -200V, TA = TMIN to TMAX, unless otherwise noted. Typical values are VDD = +3.3V, VNN = -100V, VPP = +10V at TA = +25NC.) (Note 2)
Note 2: All devices are 100% tested at TA = +85NC. Limits over the operating temperature range are guaranteed by design.
PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS
TIMING CHARACTERISTICS (Figure 2)
CLK Frequency fCLK 25 MHz
DIN to CLK Setup Time tDS 8 ns
DIN to CLK Hold Time tDH 3 ns
CLK to LE Setup Time tCS 8 ns
LE Low Pulse Width tWL 12 ns
CLR High Pulse Width tWC 12 ns
CLK Rise and Fall Times tR, tF 50 ns
CLK to DOUT Delay tDOVDD = +5V Q10%, CDOUT = 15pF 28
nsVDD = +2.5V Q5%, CDOUT = 15pF 45
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Test Circuits/Timing Diagrams
Figure 1. Test Circuits
SW_B
VDD 5V
A
ILEAK
SW_A
VPPVPP
A
ILEAK
MAX4968MAX4968A
GND
SWITCH-OFF LEAKAGE
VNNVNN
SW_B
VOUT
VDD 5V
SW_A
VPPVPP
MAX4968MAX4968A
GND
DC OFFSET ON/OFF
VNNVNN
RL100kΩ
tON/tOFF TEST CIRCUIT
SW_B
VOUT
VPP - 10V
VDD 5V
SW_A
VPPVPP
MAX4968MAX4968A
GNDVNNVNN
RL100kΩ
SW_B
VIN = 10VP-PAT 5MHz
VOUT
VDD 5V
SW_A
VPPVPP
MAX4968MAX4968A
GND
OFF-ISOLATION
VNNVNN
RL
VISO = 20logVOUT
VIN
ISOLATION DIODECURRENT
VNNSW_B
VOUT
VDD 5V
SW_A
IID
VPPVPP
MAX4968MAX4968A
GNDVNNVNN
SW_B
VIN = 10VP-PAT 5MHz
VDD 5V
SW_A
VPPVPP
MAX4968MAX4968A
GND
CROSSTALK
VNNVNN
50Ω
SW_B
SW_A50Ω
VCT = 20logVOUT
VIN
Q = 1000pF x VOUTCHARGE INJECTION
SW_B
VOUT
VOUT
100pF
VCOM_
VDD 5V
SW_A
VPPVPP
MAX4968MAX4968A
GNDVNNVNN
OUTPUT VOLTAGE SPIKE
SW_B
VOUT
+VSPK
-VSPK
VDD 5V
SW_A
VPPVPP
MAX4968MAX4968A
GNDVNNVNN
50Ω
RL1kΩ
SW_B
200pF10mVP-P
VOUTVIN
VDD 5V
SW_A
VPPVPP
MAX4968MAX4968A
GND
SMALL-SIGNALBANDWIDTH MEASUREMENT
VNNVNN
SW_B
200pF60VP-P BURST(1% DUTY CYCLE)
VOUTVIN
VDD 5V
SW_A
VPPVPP
MAX4968MAX4968A
GND
LARGE-SIGNALBANDWIDTH MEASUREMENT
VNNVNN
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Figure 2. Serial Interface Timing
Figure 3. Latch-Enable Interface Timing
Test Circuits/Timing Diagrams (continued)
DIN DN+1 DN-1DN50%
50% 50%
50%
50%50%
50%
90%
10%
50%
tCS
tWL
tDS tDH
tDO
tOFF
tWC
tON
50%
LE
CLK
DOUT
OFF
ON
SWITCH
CLR
DIN
DATA FROM PREVIOUS DATA BYTEPOWER-UP DEFAULT: D[15:0] = 0
D15
D15
D14 D13
D14 D13
D1 D0
D1 D0 D15
LSBMSB
LE
CLK
DOUT
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Typical Operating Characteristics(VDD = +3V, VPP = +10V, VNN = -100V, RL = 100I, CL = 100pF, TA = +25NC, unless otherwise noted.)
TURN-ON/TURN-OFF TIMEvs.TEMPERATURE
MAX
4968
toc0
1
TEMPERATURE (°C)
TURN
-ON/
TURN
-OFF
TIM
E (µ
s)
603510-15
1
2
3
4
5
0-40 85
tON tOFF
OFF-ISOLATION vs. FREQUENCY
MAX
4968
toc0
2
FREQUENCY (MHz)
OFF-
ISOL
ATIO
N (d
B)
1010.10.01
-80
-60
-40
-20
0
-1000.001 100
TA = -40°C
TA = +25°CTA = +85°C
SWITCH-OFF LEAKAGE CURRENTvs.TEMPERATURE
MAX
4968
toc0
3
TEMPERATURE (°C)
SWIT
CH-O
FF L
EAKA
GE C
URRE
NT (µ
A)
603510-15
0.2
0.4
0.6
0.8
1.0
0-40 85
ISW_(0FF)
HIGH-VOLTAGE SUPPLY CURRENTvs. OUTPUT SWITCH FREQUENCY
MAX
4968
toc0
7
OUTPUT SWITCH FREQUENCY (kHz)
SUPP
LY C
URRE
NT (m
A)
40302010
2
4
6
8
10
00 85
ALL SWITCHES SWITCHING
IPP (TA = +85°C)
IPP (TA = +25°C)
IPP (TA = -40°C)
INN (TA = +85°C)
INN (TA = -40°C)
INN (TA = +25°C)
LOGIC POWER-SUPPLY CURRENTvs. SERIAL-CLOCK FREQUENCY
MAX
4968
toc0
6
SERIAL-CLOCK FREQUENCY(MHz)
LOGI
C PO
WER
-SUP
PLY
CURR
ENT
(µA)
18161412108642
100
200
300
400
500
00 20
TA = +85°C
TA = +25°C
TA = +-40°C
POSITIVE AND NEGATIVE POWER-SUPPLYCURRENT vs. TEMPERATURE
MAX
4968
toc0
5
TEMPERATURE (°C)
SUPP
LY C
URRE
NT (µ
A)
603510-15
10
12
14
16
18
20
8-40 85
VPP = +10V
VNN = -100V
VNN = -70VVNN = -40V
LOGIC POWER-SUPPLY CURRENT vs.SUPPLY VOLTAGE
MAX
4968
toc0
4
VDD SUPPLY VOLTAGE (V)
LOGI
C PO
WER
-SUP
PLY
CURR
ENT
(µA)
5.14.74.33.93.53.12.7
0.5
1.0
1.5
2.0
2.5
3.0
02.3 5.5
TA = -40°C
TA = +25°C
TA = +85°C
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Pin Configuration
Pin Description
TOP VIEW
LQFP(7mm × 7mm)
+13
14
15
16
17
18
19
20
21
22
23
24
VNN
N.C.
VPP
N.C.
GND
VDD
DIN
CLK
LE
CLR
DOUT
N.C.
48
47
46
45
44
43
42
41
40
39
38
37
1 2 3 4 5 6 7 8 9 10 11 12
SW5A
SW5B
SW6A
SW6B
SW7A
SW7B
SW8A
SW8B
SW9A
SW9B
SW10A
SW10B
SW0A
SW0B
SW1A
SW1B
SW2A
SW2B
SW3A
SW3B
SW4A
SW4B
N.C.
N.C.
36 35 34 33 32 31 30 29 28 27 26 25
SW15
B
SW15
A
SW14
B
SW14
A
SW13
B
SW13
A
SW12
B
SW12
A
SW11
B
SW11
A
N.C.
N.C.
MAX4968MAX4968A
PIN NAME FUNCTION
1, 2, 14, 16, 24, 35, 36
N.C.No Connection. Not connected internally.
3 SW4B Analog Switch 4—Terminal
4 SW4A Analog Switch 4—Terminal
5 SW3B Analog Switch 3—Terminal
6 SW3A Analog Switch 3—Terminal
7 SW2B Analog Switch 2—Terminal
8 SW2A Analog Switch 2—Terminal
9 SW1B Analog Switch 1 —Terminal
10 SW1A Analog Switch 1—Terminal
11 SW0B Analog Switch 0—Terminal
12 SW0A Analog Switch 0—Terminal
13 VNN
Negative High-Voltage Supply. Bypass VNN to GND with a 0.1FF or greater ceramic capacitor.
PIN NAME FUNCTION
15 VPP
Positive Voltage Supply. Bypass VPP to GND with a 0.1FF or greater ceramic capacitor.
17 GND Ground
18 VDD
Logic Supply Voltage. Bypass VDD to GND with a 0.1FF or greater ceramic capacitor.
19 DIN Serial-Data Input
20 CLK Serial-Clock Input
21 LE Active-Low Latch-Enable Input
22 CLR Latch-Clear Input
23 DOUT Serial-Data Output
25 SW15B Analog Switch 15—Terminal
26 SW15A Analog Switch 15—Terminal
27 SW14B Analog Switch 14—Terminal
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Detailed DescriptionThe MAX4968/MAX4968A are 16-channel, high-linearity, high-voltage, bidirectional SPST analog switches with 18I (typ) on-resistance. The devices are ideal for use in applications requiring high-voltage switching controlled by a low-voltage control signal, such as ultrasound imag-ing and printers. The MAX4968A provides integrated 40kI (typ) bleed resistors on each switch terminal to discharge capacitive loads. Using HVCMOS technol-ogy, these switches combine high-voltage, bilateral MOS switches and low-power CMOS logic to provide efficient control of high-voltage analog signals.
The MAX4968 is pin-to-pin compatible with the MAX14802 and Supertex HV2601. The MAX4968A is pin-to-pin compatible with the MAX14803 and Supertex HV2701. The only difference is the VPP positive supply voltage level. The MAX4968/MAX4968A require a low +10V (typ) voltage (VPP), whereas the MAX14802/MAX14803 and HV2601/HV2701 require a high +100V supply voltage.
In typical ultrasound applications, these devices do not require dedicated high-voltage supply, which implies a significant simplification of system requirement. The negative voltage supply can be shared with the transmit-ter and the positive voltage supply is typically +10V.
Analog SwitchThe devices can transmit analog signals up to 210VP-P, with an analog signal range from VNN to VNN + 210V. Before starting the high-voltage burst transmission (VP-P > +20V), the input voltage is required to be close to GND to allow a proper settling of the pass FET. The high-voltage burst frequency must be greater than 500kHz.
Extremely long high-voltage bursts (VP-P > +10V) with duty cycle greater than 20% could result in signal deg-radation, especially for unipolar transmission. In general, this applies for burst transmission with a nonzero DC content.
Low-voltage signal (VP-P < 10V) continuous-wave bipo-lar transmission is supported for frequencies greater than 500kHz. For very small signals, such as the small echoes in typical ultrasound imaging systems (VP-P < 10V), the devices are not limited to a low-frequency bandwidth and can transmit DC signals.
Voltage SuppliesThe devices operate with a high-voltage supply VNN from -200V to 0, VPP supply of +10V (typ), and a logic supply VDD (+2.37V to +5.5V).
Pin Description (continued)
PIN NAME FUNCTION
28 SW14A Analog Switch 14—Terminal
29 SW13B Analog Switch 13—Terminal
30 SW13A Analog Switch 13—Terminal
31 SW12B Analog Switch 12—Terminal
32 SW12A Analog Switch 12—Terminal
33 SW11B Analog Switch 11—Terminal
34 SW11A Analog Switch 11—Terminal
37 SW10B Analog Switch 10—Terminal
38 SW10A Analog Switch 10—Terminal
39 SW9B Analog Switch 9—Terminal
PIN NAME FUNCTION
40 SW9A Analog Switch 9—Terminal
41 SW8B Analog Switch 8—Terminal
42 SW8A Analog Switch 8—Terminal
43 SW7B Analog Switch 7—Terminal
44 SW7A Analog Switch 7—Terminal
45 SW6B Analog Switch 6—Terminal
46 SW6A Analog Switch 6—Terminal
47 SW5B Analog Switch 5—Terminal
48 SW5A Analog Switch 5—Terminal
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Bleed Resistors (MAX4968A)The MAX4968A features integrated 40kI (typ) bleed resistors to discharge capacitive loads such as piezo-electric transducers. Each analog switch terminal is con-nected to GND with a bleed resistor.
Serial InterfaceThe MAX4968/MAX4968A are controlled by a serial interface with a 16-bit serial shift register and transparent latch. Each of the 16 data bits controls a single analog switch (see Table 1). Data on DIN is clocked with the most significant bit (MSB) first into the shift register on the rising edge of CLK. Data is clocked out of the shift register onto DOUT on the rising edge of CLK. DOUT reflects the status of DIN, delayed by 16 clock cycles (see Figures 2 and 3).
Latch Enable (LE)Drive LE logic-low to change the contents of the latch and update the state of the high-voltage switches
(Figure 3). Drive LE logic-high to freeze the contents of the latch and prevent changes to the switch states. To reduce noise due to clock feedthrough, drive LE logic-high while data is clocked into the shift register. After the data shift register is loaded with valid data, pulse LE logic-low to load the contents of the shift register into the latch.
Latch Clear (CLR)The MAX4968/MAX4968A feature a latch-clear input. Drive CLR logic-high to reset the contents of the latch to zero and open all switches. CLR does not affect the contents of the data shift register. Pulse LE logic-low to reload the contents of the shift register into the latch.
Power-On ResetThe MAX4968/MAX4968A feature a power-on-reset cir-cuit to ensure all switches are open at power-on. The internal 16-bit serial shift register and latch are set to zero on power-up.
Table 1. Serial Interface Programming (Notes 1–6)
DATA BITSCONTROL
BITSFUNCTION
D0(LSB)
D1 D2 D3 D4 D5 D6 D7 LE CLR SW0 SW1 SW2 SW3 SW4 SW5 SW6 SW7
L L L Off
H L L On
L L L Off
H L L On
L L L Off
H L L On
L L L Off
H L L On
L L L Off
H L L On
L L L Off
H L L On
L L L Off
H L L On
L L L Off
H L L On
X X X X X X X X H L Hold Previous State
X X X X X X X X X H Off Off Off Off Off Off Off Off
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Table 1. Serial Interface Programming (Notes 1–6) (continued)
Note 1: The 16 switches operate independently.Note 2: Serial data is clocked in on the rising edge of CLK.Note 3: The switches go to a state retaining their present condition on the rising edge of LE. When LE is low, the shift register data
flows through the latch.Note 4: DOUT is high when switch 15 is on.Note 5: Shift register clocking has no effect on the switch states if LE is high.Note 6: The CLR input overrides all other inputs.
Applications InformationIn typical ultrasound applications, the MAX4968/MAX4968A do not require dedicated high-voltage supplies; the nega-tive voltage supply can be shared with the transmitter and the positive voltage supply is typically +10V. See Figures 5, 6, and 7 for medical ultrasound applications.
Logic LevelsThe MAX4968/MAX4968A digital interface inputs CLK, DIN, LE, and CLR operate on the VDD logic supply voltage.
Daisy-Chaining Multiple DevicesDigital output DOUT is provided to allow the connec-tion of multiple MAX4968/MAX4968A devices by daisy-
chaining (Figure 4). Connect each DOUT to the DIN of the subsequent device in the chain. Connect CLK, LE, and CLR inputs of all devices, and drive LE logic-low to update all devices simultaneously. Drive CLR high to open all the switches simultaneously. Additional shift registers can be included anywhere in series with the MAX4968/MAX4968A daisy-chain.
Supply Sequencing and BypassingThe MAX4968/MAX4968A do not require special sequencing of the VDD, VPP, and VNN supply voltages. Bypass VDD, VPP, and VNN to GND with a 0.1FF ceramic capacitor as close as possible to the device.
Note: Keep LE low during power-up.
DATA BITSCONTROL
BITSFUNCTION
D8 D9 D10 D11 D12 D13 D14D15
(MSB) LE CLR SW8 SW9 SW10 SW11 SW12 SW13 SW14 SW15
L L L Off
H L L On
L L L Off
H L L On
L L L Off
H L L On
L L L Off
H L L On
L L L Off
H L L On
L L L Off
H L L On
L L L Off
H L L On
L L L Off
H L L On
X X X X X X X X H L Hold Previous State
X X X X X X X X X H Off Off Off Off Off Off Off Off
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Application Diagrams
Figure 4. Interfacing Multiple Devices by Daisy-Chaining
CLK
DIN
CLK
LE
CLR
U10 U11 U1n
U20 U21 U2n
DOUTDIN1
LE
CLR
DIN2 DIN
CLK
LE
CLR
DOUT DIN
CLK
LE
CLR
DOUT DIN
CLK
LE
CLR
DOUT
DIN
CLK
LE
CLR
DOUT DIN
CLK
LE
CLR
DOUT
MAX4968MAX4968A
MAX4968MAX4968A
MAX4968MAX4968A
MAX4968MAX4968A
MAX4968MAX4968A
MAX4968MAX4968A
MA
X4
96
8/M
AX
49
68
A
16-Channel, Linear, High-Voltage Analog Switches
13
Application Diagrams (continued)
Figure 5. Medical Ultrasound Application—High-Voltage Analog Switches in Probe
HIGH-VOLTAGE TRANSMIT1 PER CHANNEL
PROBE SELECTION2 TO 4 PROBES
RELAY1 RELAY/CH/PROBE
CABLE1 PER CHANNEL
TRANSDUCERS2 TO 4 PER CHANNEL
HIGH-VOLTAGE ANALOGSWITCHES
2 TO 4 PER CHANNEL
±100V MAX ±1 TO 2A MAX
MAINFRAME
+V
-V
PROBES
±1V MAX
10mA TYP
HIGH-VOLTAGEISOLATION
LOW-VOLTAGE RECEIVE64 TO 128 CHANNELS
PROBEB
PROBEA
PROBEC
PROBED
MA
X4
96
8/M
AX
49
68
A
16-Channel, Linear, High-Voltage Analog Switches
14
Application Diagrams (continued)
Figure 6. Medical Ultrasound Application—High-Voltage Analog Switches in Mainframe
PROBEA
HIGH-VOLTAGETRANSMIT
1 PER CHANNEL
PROBE SELECTION2 TO 4 PROBES
RELAYS2 TO 4 RELAYS/CH/PROBE
CABLE2 TO 4 PER CHANNEL
TRANSDUCERS2 TO 4 PER CHANNEL
HIGH-VOLTAGE ANALOGSWITCHES
2 TO 4 PER CHANNEL±100V MAX ±1 TO 2A MAX
MAINFRAME
+V
-V
PROBES
±1V MAX
10mA TYP
HIGH-VOLTAGEISOLATION
LOW-VOLTAGE RECEIVE
64 TO 128 CHANNELS
PROBEB
PROBEC
PROBED
MA
X4
96
8/M
AX
49
68
A
16-Channel, Linear, High-Voltage Analog Switches
15
Application Diagrams (continued)
Figure 7. Medical Ultrasound Application—Multiple Transmit and Isolation per Receiver Channel
PROBEA
HIGH-VOLTAGE TRANSMIT2 TO 4 PER CHANNEL
HIGH-VOLTAGEISOLATION ANDCHANNEL SELECT2 TO 4 PER CHANNEL
LOW-VOLTAGE RECEIVE64 TO 128 CHANNELS
PROBE SELECTION2 TO 4 PROBES
RELAYS2 TO 4 RELAYS/CH/PROBE
CABLE2 TO 4 PER CHANNEL
TRANSDUCERS2 TO 4 PER CHANNEL
±100V MAX ±1 TO 2A MAX
MAINFRAME
+V
-V
PROBES
±1V MAX
10mA TYP
PROBEB
PROBEC
PROBED
+V
-V
+V
-V
+V
-V
+V
-V
+V
-V
+V
-V
+V
-V
MA
X4
96
8/M
AX
49
68
A
16-Channel, Linear, High-Voltage Analog Switches
16
Functional Diagram
Chip InformationPROCESS: BiCMOS
Package InformationFor the latest package outline information and land patterns (footprints), go to www.maxim-ic.com/packages. Note that a “+”, “#”, or “-“ in the package code indicates RoHS status only. Package drawings may show a different suffix character, but the drawing pertains to the package regardless of RoHS status.
16-BITSHIFT
REGISTER
LATCH
VDD VPP
*BLEED RESISTORS AVAILABLE ON THE MAX4968A ONLY.
GND VNN
LEVELSHIFTER
CLR
SW0B
SW0AVNN
*
*
VNN
DIN
CLK
DOUT
LE
LATCHLEVEL
SHIFTER
SW15B
SW15AVNN
*
*
VNN
MAX4968MAX4968A
PACKAGE TYPE
PACKAGE CODE
OUTLINE NO.
LAND PATTERN NO.
48 LQFP C48+6 21-0054 90-0093
Maxim cannot assume responsibility for use of any circuitry other than circuitry entirely embodied in a Maxim product. No circuit patent licenses are implied. Maxim reserves the right to change the circuitry and specifications without notice at any time.
Maxim Integrated Products, 120 San Gabriel Drive, Sunnyvale, CA 94086 408-737-7600 17
© 2012 Maxim Integrated Products Maxim is a registered trademark of Maxim Integrated Products, Inc.
MA
X4
96
8/M
AX
49
68
A
16-Channel, Linear, High-Voltage Analog Switches
Revision History
REVISIONNUMBER
REVISIONDATE
DESCRIPTIONPAGES
CHANGED
0 3/11 Initial release —
1 5/11Removed future product asterisk from MAX4968 in Ordering Information, corrected Off-Isolation specification in Electrical Characteristics
1, 3
2 1/12Updated VNN specifications in Absolute Maximum Ratings and Electrical Characteristics supply voltage and VNN static current specifications
2, 3, 4, 9