Temperature Measurement Circuits for Embedded Applications
This application note shows how to select a temperature sensor and conditioning circuit to maximize the
measurement accuracy and simplify the interface to the microcontroller. Practical circuits and interface
techniques will be provided for embedded applications with thermocouples, Resistive Temperature Detectors (RTDs), thermistors and silicon integrated circuit temperature sensors. The attributes of each temperature sensor and the advantages of analog, frequency, ramp rate, duty cycle, serial and logic output solutions
will be discussed. An analog output thermocouple circuit will be compared with a frequency output RTD oscillator circuit, along with design examples using serial and analog output silicon Integrated Circuit (IC) sensors. In addition, a Programmable Gain Amplifier
(PGA) circuit will be shown that can increase the effectiveness of the Analog-to-Digital Converter (ADC)
bit resolution of a non-linear thermistor sensor.
temperature sesors,thermal sensor,silicon temperature sensor,operational amplifier,op amp,Analog-to-PIC interface