PRACTICAL DESIGN TECHNIQUES FOR SENSOR SIGNAL CONDITIONING

Transcription

1 PRACTICAL DESIGN TECHNIQUES FOR SENSOR SIGNAL CONDITIONING INTRODUCTION - BRIDGE CIRCUITS - AMPLIFIERS FOR SIGNAL CONDITIONING - STRAIN, FORCE, PRESSURE, AND FLOW MEASUREMENTS - HIGH IMPEDANCE SENSORS - POSITION AND MOTION SENSORS - TEMPERATURE SENSORS - ADCs FOR SIGNAL CONDITIONING - SMART SENSORS - HARDWARE DESIGN TECHNIQUES - INDEX I

2 ANALOG DEVICES TECHNICAL REFERENCE BOOKS PUBLISHED BY PRENTICE HALL Analog-Digital Conversion Handbook Digital Signal Processing Applications Using the ADSP-2100 Family (Volume 1:1992, Volume 2:1994) Digital Signal Processing in VLSI DSP Laboratory Experiments Using the ADSP-2101 ADSP-2100 Family User's Manual PUBLISHED BY ANALOG DEVICES Practical Design Techniques for Power and Thermal Management High Speed Design Techniques Practical Analog Design Techniques Linear Design Seminar ADSP Family Applications Handbook System Applications Guide Applications Reference Manual Amplifier Applications Guide Mixed Signal Design Seminar Notes High-Speed Design Seminar Notes Nonlinear Circuits Handbook Transducer Interfacing Handbook Synchro & Resolver Conversion THE BEST OF Analog Dialogue,

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4 India Call or fax and request the data sheet of interest. Other Locations World Wide Web. Our address is Use the browser of your choice and follow the prompts. Analog Devices Sales Offices. Call your local sales office and request a data sheet. A Worldwide Sales Directory including telephone numbers is listed on the back cover of the 1997 Short Form Designers' Guide. TECHNICAL SUPPORT AND CUSTOMER SERVICE In the U.S.A. and Canada, call 800-ANALOGD, ( ). For technical support on all products, select option one, then select the product area of interest. For price and delivery, select option three. For literature and samples, select option two. Non-800 Number:

5 PRACTICAL DESIGN TECHNIQUES FOR SENSOR SIGNAL CONDITIONING a

6 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. Special thanks go to Wes Freeman, Walter G. Jung, Bill Chestnut, and Ed Grokulsky for thoroughly reviewing the material for content and accuracy. Judith Douville compiled the index, and printing was done by R. R. Donnelley and Sons, Inc. Copyright 1999 by Analog Devices, Inc. Printed in the United States of America Walt Kester 1999 All rights reserved. This book, or parts thereof, must not be reproduced in any form without permission of the copyright owner. Information furnished by Analog Devices, Inc., is believed to be accurate and reliable. However, no responsibility is assumed by Analog Devices, Inc., for its use. Analog Devices, Inc., makes no representation that the interconnections of its circuits as described herein will not infringe on existing or future patent rights, nor do the descriptions contained herein imply the granting of licenses to make, use, or sell equipment constructed in accordance therewith. Specifications are subject to change without notice. ISBN

7 PRACTICAL DESIGN TECHNIQUES FOR SENSOR SIGNAL CONDITIONING SECTION 1 INTRODUCTION SECTION 2 BRIDGE CIRCUITS Bridge Configurations Amplifying and Linearizing Bridge Outputs Driving Bridges SECTION 3 AMPLIFIERS FOR SIGNAL CONDITIONING Precision Op Amp Characteristics Amplifier DC Error Budget Analysis Single Supply Op Amps Instrumentation Amplifiers Chopper Stabilized Amplifiers Isolation Amplifiers

8 SECTION 4 STRAIN, FORCE, PRESSURE, AND FLOW MEASUREMENTS Strain Gages Bridge Signal Conditioning Circuits SECTION 5 HIGH IMPEDANCE SENSORS Photodiode Preamplifier Design Compensation of High Speed Photodiode I/V Converter High Impedance Charge Output Sensors CCD/CIS Image Processing SECTION 6 POSITION AND MOTION SENSORS Linear Variable Differential Transformers (LVDTs) Hall Effect Magnetic Sensors Optical Encoders Resolvers and Synchros Inductosyns Vector AC Induction Motor Control Accelerometers

9 SECTION 7 TEMPERATURE SENSORS Thermocouple Principles and Cold-Junction Compensation Resistance Temperature Detectors (RTDs) Thermistors Semiconductor Temperature Sensors Microprocessor Temperature Monitoring SECTION 8 ADCs FOR SIGNAL CONDITIONING Successive Approximation ADCs SAR ADCs With Multiplexed Inputs Complete Data Acquisition Systems on a Chip Sigma-Delta Measurement ADCs High Resolution, Low-Frequency Sigma-Delta Measurement ADCs Applications of Sigma-Delta ADCs in Power Meters

10 SECTION 9 SMART SENSORS 4-20mA Control Loops Interfacing Sensors to Networks MicroConverter SECTION 10 HARDWARE DESIGN TECHNIQUES Resistor and Thermocouple Errors in High Accuracy Systems Grounding in Mixed Signal Systems Power Supply Noise Reduction and Filtering Preventing RFI Rectification Dealing With High Speed Logic A Review of Shielding Concepts Isolation Techniques Overvoltage Protection Electrostatic Discharge (ESD) INDEX

11 PRACTICAL DESIGN TECHNIQUES FOR SENSOR SIGNAL CONDITIONING INTRODUCTION - BRIDGE CIRCUITS - AMPLIFIERS FOR SIGNAL CONDITIONING - STRAIN, FORCE, PRESSURE, AND FLOW MEASUREMENTS - HIGH IMPEDANCE SENSORS - POSITION AND MOTION SENSORS - TEMPERATURE SENSORS - ADCs FOR SIGNAL CONDITIONING - SMART SENSORS - HARDWARE DESIGN TECHNIQUES - INDEX I

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