Interfacing PIC Microcontrollers

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Sensor Interfacing

A wide variety of sensors are used in digital control systems and interfacing

them requires a good understanding of linear amplifier design and signal con-

ditioning techniques. Connection to an MCU is simplified if the sensor itself

contains built-in signal conditioning, such that the output is linear, reasonably

large, conveniently scaled and pre-calibrated. The LM35 temperature sensor is

a good example, giving an output of 10 mV/°C, starting at 0°C ⫽ 0 mV, but it

needs an ADC input. Increasingly, sensors are incorporating all the necessary

signal processing and serial data outputs, so that interface design is simplified

or eliminated. ...