The PT100 RTD Temperature Sensor Amplifier is an easy-to-use thermistor to digital output converter optimized for platinum resistance temperature detectors (RTD).
For precision temperature sensing, nothing beats a Platinum RTD. RTD is a temperature sensor that contain a resistor that changes resistance value as its temperature changes. It is basically a kind of thermistor.
In this RTD sensor, the resistor is actually a small strip of Platinum with a resistance of 100 ohms at 0°C, thus the name PT100. You can also use this sensor to measure any kind of variable resistor that has about 100 ohm of resistance (but can range from half to double that)
Compared to most NTC/PTC thermistors, the PT type of RTD is much most stable. It is also precise (but also more expensive) PT100 have been used for many years to measure temperature in laboratory and industrial processes. It has also developed a reputation for accuracy (better than thermocouples), repeatability, and stability.
However, to get that precision and accuracy out of your PT100 RTD you must use an amplifier that is designed to read the low resistance. Better yet, have an amplifier that can automatically adjust and compensate for the resistance of the connecting wires.
IWe have carried various MAXIM thermocouple amplifiers and they’re great. But thermocouples don’t have the best accuracy or precision, for when the readings must be as good as can be. The MAX31865 handles all of your RTD needs. It can even compensate 3 or 4 wire RTDs for better accuracy. Connect to it with any microcontroller over SPI and read out the resistance ratio from the internal ADC.
1 x PT100 RTD Temperature Sensor Amplifier Module