mid-semester presentation senior design 1 october 8, 2009
TRANSCRIPT
Mid-Semester PresentationMid-Semester Presentation
Senior Design 1Senior Design 1
October 8, 2009October 8, 2009
Randall Vaughan
Oscillator Interface
Layout and Design
Electrical Engineering
Caroline Quijano
Op-Amp Configuration
Layout and Design
Electrical Engineering
Zach Jordan
Op-Amp ConfigurationPhase Shift Detection
Computer Engineering
Jonathan Lynch
Oscillator InterfaceWebsite DesignCircuit Board Production
Electrical Engineering
ProblemProblem SolutionSolution ConstraintsConstraints
• TechnicalTechnical• PracticalPractical
AlternativesAlternatives ProgressProgress
Dr. Jack Liu of the Department of Dr. Jack Liu of the Department of Forestry Products requires the use of Forestry Products requires the use of a portable RF moisture content a portable RF moisture content sensorsensor
Needs a smaller, inexpensive, Needs a smaller, inexpensive, repackage of his patented prototype repackage of his patented prototype
The moisture content sensor will apply a high frequency sine wave using a XR2206 waveform generator, two PS-05 48V power supplies, and a PA78 350V operational amplifier .
The resultant phase shift and attenuation measurements between the applied and received signal will be used to compute the moisture content.
MC= -11403+1665.637Att – 80.843Att^2 + 1.305Att^3 + 0.571Phase^2
Power Supply
Operational Amplifier
PIC 24Waveform Generator
LCD Screen
Transmitting/Receiving
Sensors
Technical ConstraintsTechnical Constraints
Practical ConstraintsPractical Constraints
Constraint Description
Voltage LevelThe signal applied to the sensors must measure 80V (+/- 5V) peak-to-peak.
Frequency The sensor must produce a 250 kHz (+/- 5 kHz) sine wave.
InterfaceThe device must have a simple user interface in order to display its measurements.
Data LoggingThe device must be able to store at least 130 kilobytes of moisture content readings.
Sensor ArrayThe device must use seven 4 in. by 4 in. sensors configured in an array.
Type Constraint Description
Environmental DurabilityThe device must be able to withstand various industrial conditions such as dust and electrical noise.
Health and Safety
SafetyUser contact with high voltage signals must be prevented.
Sensor must Sensor must withstand debris, withstand debris, electrical noise, electrical noise, and moistureand moisture
Sealed, electrically Sealed, electrically shielded, rugged shielded, rugged housinghousing
[5]
Isolated high Isolated high voltagesvoltages
Partition that Partition that separates gap separates gap from user from user interfaceinterface
Appropriate Appropriate warning labels warning labels displayeddisplayed
[6]
Power SuppliesPower Supplies
Sine Wave GenerationSine Wave Generation
Operational AmplifiersOperational Amplifiers
Phase Shift DetectionPhase Shift Detection
Mean Well PS-05Mean Well PS-05• Pros: Supplies +/-48 volts, Inexpensive, Easily-Accessible, Pros: Supplies +/-48 volts, Inexpensive, Easily-Accessible,
Low Power Dissipation, AC/DC SwitchingLow Power Dissipation, AC/DC Switching• Cons: Requires Separate CablesCons: Requires Separate Cables
Charge PumpCharge Pump• Pros: High Efficiency, Electrically-Simple CircuitsPros: High Efficiency, Electrically-Simple Circuits• Cons: High Current DrawCons: High Current Draw
DC/DC ConverterDC/DC Converter• Pros: Regulates Output VoltagePros: Regulates Output Voltage• Cons: Several Sub-Circuits (each with its own voltage Cons: Several Sub-Circuits (each with its own voltage
level requirement different from the external source)level requirement different from the external source)
XR2206 Waveform GeneratorXR2206 Waveform Generator• Pros: Frequency easily set by a resistor and capacitor, excellent Pros: Frequency easily set by a resistor and capacitor, excellent
temperature stability (20ppm/deg C)temperature stability (20ppm/deg C)• Cons: Requires a minimum 10V supply voltageCons: Requires a minimum 10V supply voltage
DS1077 Programmable OscillatorDS1077 Programmable Oscillator• Pros: I2C Interface, Inexpensive, Dual Output, Programmable Pros: I2C Interface, Inexpensive, Dual Output, Programmable
Frequencies 8.1kHz – 133MHzFrequencies 8.1kHz – 133MHz• Cons: Does not output a sine waveCons: Does not output a sine wave
Analog Edge Sine Wave GenerationAnalog Edge Sine Wave Generation• Pros: Simple Circuit, InexpensivePros: Simple Circuit, Inexpensive• Cons: Sine Wave Distortion, Square Wave GenerationCons: Sine Wave Distortion, Square Wave Generation
Resonant CrystalResonant Crystal• Pros: Very accurate, High precision, StablePros: Very accurate, High precision, Stable• Cons: Comes with a fixed frequency, unchangeable Cons: Comes with a fixed frequency, unchangeable
PA78 350V Op-AmpPA78 350V Op-Amp• Pros: Has High Voltage Specification, High Slew Rate for Pros: Has High Voltage Specification, High Slew Rate for
Phase Shift, Low Idle CurrentPhase Shift, Low Idle Current
OPA445 90V Op-AmpOPA445 90V Op-Amp• Pros: Meets minimum requirements for voltage Pros: Meets minimum requirements for voltage
specificationspecification• Cons: Low slew rateCons: Low slew rate
OPA453 80V 50mA Op-AmpOPA453 80V 50mA Op-Amp• Pros: Has high slew ratePros: Has high slew rate• Cons: Does not meet rail-to-rail voltage specificationCons: Does not meet rail-to-rail voltage specification
Zero Crossing Zero Crossing CircuitsCircuits
Logic GatesLogic Gates
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AugustAugust SeptemberSeptember OctoberOctober NovemberNovember
ResearchResearch
Hardware Hardware
DesignDesign
PrototypingPrototyping
TestingTesting
Programmed DS1077 Oscillator to Programmed DS1077 Oscillator to 250 kHz250 kHz
Ordered Power SuppliesOrdered Power Supplies
PA78 350V Operational AmplifierPA78 350V Operational Amplifier• Designed alternative feedback loopsDesigned alternative feedback loops
PIC 24
DS1077 Programmable Oscillator
XR2206 Waveform Generator
Mean Well Mean Well PS-05PS-05
[1] United States of America. Federal Communications Commission. [1] United States of America. Federal Communications Commission. Code of Code of Federal Regulations, Title 47, Part 15.Federal Regulations, Title 47, Part 15. Washington, D.C.: Federal Communications Washington, D.C.: Federal Communications Commission, 2008. Commission, 2008.
[2] Panel Layup Operations, by Phil Mitchell, Raleigh, NC. [Online] Available: [2] Panel Layup Operations, by Phil Mitchell, Raleigh, NC. [Online] Available: http://www.ces.ncsu.edu/nreos/wood/RMOG/Adobe/Panel.pdfhttp://www.ces.ncsu.edu/nreos/wood/RMOG/Adobe/Panel.pdf..
[3] Forestry Facts: Guide for Using the Oven-Dry Method for Determining the [3] Forestry Facts: Guide for Using the Oven-Dry Method for Determining the Moisture Content of Wood, by R.S Boone and E.M. Wengert, Madison, Wisconsin, Moisture Content of Wood, by R.S Boone and E.M. Wengert, Madison, Wisconsin, 1998. [Online] Available:1998. [Online] Available:
http://forest.wisc.edu/extension/Publications/89.pdfhttp://forest.wisc.edu/extension/Publications/89.pdf..
[4] Wood Products Notes: Methods of Moisture Content Measurement in the [4] Wood Products Notes: Methods of Moisture Content Measurement in the Lumber and Furniture Industries, by Phil Mitchell, Raleigh, NC. [Online]Available: Lumber and Furniture Industries, by Phil Mitchell, Raleigh, NC. [Online]Available: http://www.ces.ncsu.edu/nreos/wood/wpn/methods_moisture.htmhttp://www.ces.ncsu.edu/nreos/wood/wpn/methods_moisture.htm. .
[5] Google Images. 2009. [5] Google Images. 2009. http://www.waltsense.com/storage/articles/20090429_finger-in-socket.jpg.http://www.waltsense.com/storage/articles/20090429_finger-in-socket.jpg.
[6] Microsoft Office Online, Clip Art. 2009. [6] Microsoft Office Online, Clip Art. 2009. http://office.microsoft.com/en-us/clipart/results.aspx?qu=warning&sc=20http://office.microsoft.com/en-us/clipart/results.aspx?qu=warning&sc=20..
[7] Phase Shift. Algebra 2 Trig., by Donna Roberts. Copyright 1998-2009. [7] Phase Shift. Algebra 2 Trig., by Donna Roberts. Copyright 1998-2009. http://www.regentsprep.org/Regents/math/algtrig/ATT7/phaseshift.htmhttp://www.regentsprep.org/Regents/math/algtrig/ATT7/phaseshift.htm..