Understanding Smart Sensors - Nomads.usp

Contentsix3.3.3 Hall Effect 603.3.4 Chemical Sensors 603.3.5 Improving Sensor Characteristics 613.4 Digital Output Sensors 623.4.1 Incremental Optical Encoders 633.4.2 Digital Techniques 643.5 Noise/Interference Aspects 653.6 Low-Power, Low-Voltage Sensors 663.6.1 Impedance 673.7 Analysis of Sensitivity Improvement 673.7.1 Thin Diaphragm 673.7.2 Increased Diaphragm Area 673.7.3 Combined Solution: Micromachining andMicroelectronics 683.8 Summary 68References 694 Getting Sensor Information Into the MCU 714.1 Introduction 714.2 Amplification and Signal Conditioning 724.2.1 Instrumentation Amplifiers 734.2.2 SLEEPMODE Operational Amplifier 754.2.3 Rail-to-Rail Operational Simplifiers 764.2.4 Switched-Capacitor Amplifier 774.2.5 Barometer Application Circuit 794.2.6 4- to 20-mA Signal Transmitter 794.2.7 Schmitt Trigger 794.2.8 Inherent Power-Supply Rejection 814.3 Separate Versus Integrated Signal Conditioning 824.3.1 Integrated Passive Elements 834.3.2 Integrated Active Elements 844.4 Digital Conversion 86