PRACTICAL DESIGN TECHNIQUES
FOR SENSOR SIGNAL CONDITIONING
INTRODUCTION -
1
BRIDGE CIRCUITS -
2
AMPLIFIERS FOR SIGNAL CONDITIONING -
3
STRAIN, FORCE, PRESSURE, AND FLOW MEASUREMENTS -
4
HIGH IMPEDANCE SENSORS -
5
POSITION AND MOTION SENSORS -
6
TEMPERATURE SENSORS -
7
ADCs FOR SIGNAL CONDITIONING -
8
SMART SENSORS -
9
HARDWARE DESIGN TECHNIQUES INDEX -
10
I
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PRACTICAL DESIGN TECHNIQUES
FOR SENSOR
SIGNAL CONDITIONING
a
ACKNOWLEDGMENTS
Thanks are due the many technical staff members of Analog Devices in Engineering and
Marketing who provided invaluable inputs during this project. Particular credit is due the
individual authors whose names appear at the beginning of their material.
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thoroughly reviewing the material for content and accuracy.
Judith Douville compiled the index, and printing was done by R. R. Donnelley and Sons, Inc.
Walt Kester
1999
Copyright  1999 by Analog Devices, Inc.
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Specifications are subject to change without notice.
ISBN-0-916550-20-6
PRACTICAL DESIGN TECHNIQUES FOR
SENSOR SIGNAL CONDITIONING
SECTION 1
INTRODUCTION
SECTION 2
BRIDGE CIRCUITS
n
Bridge Configurations
n
Amplifying and Linearizing Bridge Outputs
n
Driving Bridges
SECTION 3
AMPLIFIERS FOR SIGNAL CONDITIONING
n
Precision Op Amp Characteristics
n
Amplifier DC Error Budget Analysis
n
Single Supply Op Amps
n
Instrumentation Amplifiers
n
Chopper Stabilized Amplifiers
n
Isolation Amplifiers
SECTION 4
STRAIN, FORCE, PRESSURE, AND FLOW MEASUREMENTS
n
Strain Gages
n
Bridge Signal Conditioning Circuits
SECTION 5
HIGH IMPEDANCE SENSORS
n
Photodiode Preamplifier Design
n
Compensation of High Speed Photodiode
I/V Converter
n
High Impedance Charge Output Sensors
n
CCD/CIS Image Processing
SECTION 6
POSITION AND MOTION SENSORS
n
Linear Variable Differential Transformers (LVDTs)
n
Hall Effect Magnetic Sensors
n
Optical Encoders
n
Resolvers and Synchros
n
Inductosyns
n
Vector AC Induction Motor Control
n
Accelerometers
SECTION 7
TEMPERATURE SENSORS
n
Thermocouple Principles and Cold-Junction
Compensation
n
Resistance Temperature Detectors (RTDs)
n
Thermistors
n
Semiconductor Temperature Sensors
n
Microprocessor Temperature Monitoring
SECTION 8
ADCs FOR SIGNAL CONDITIONING
n
Successive Approximation ADCs
n
SAR ADCs With Multiplexed Inputs
n
Complete Data Acquisition Systems on a Chip
n
Sigma-Delta Measurement ADCs
n
High Resolution, Low-Frequency Sigma-Delta
Measurement ADCs
n
Applications of Sigma-Delta ADCs in
Power Meters
SECTION 9
SMART SENSORS
n
4-20mA Control Loops
n
Interfacing Sensors to Networks
n
MicroConverter™
SECTION 10
HARDWARE DESIGN TECHNIQUES
n
Resistor and Thermocouple Errors in
High Accuracy Systems
n
Grounding in Mixed Signal Systems
n
Power Supply Noise Reduction and Filtering
n
Preventing RFI Rectification
n
Dealing With High Speed Logic
n
A Review of Shielding Concepts
n
Isolation Techniques
n
Overvoltage Protection
n
Electrostatic Discharge (ESD)
INDEX
PRACTICAL DESIGN TECHNIQUES
FOR SENSOR SIGNAL CONDITIONING
INTRODUCTION -
1
BRIDGE CIRCUITS -
2
AMPLIFIERS FOR SIGNAL CONDITIONING -
3
STRAIN, FORCE, PRESSURE, AND FLOW MEASUREMENTS -
4
HIGH IMPEDANCE SENSORS -
5
POSITION AND MOTION SENSORS -
6
TEMPERATURE SENSORS -
7
ADCs FOR SIGNAL CONDITIONING -
8
SMART SENSORS -
9
HARDWARE DESIGN TECHNIQUES INDEX -
10
I