Temperature Sensors Monitor (TMS) interface
Temperature monitor channels are resistance measurement channels used for resistive temperature sensor acquisition. The word “thermistor” is derived from the description “thermally sensitive resistor”. Thermistors are further classified as “Positive Temperature Coefficient” devices (PTC devices) or “Negative Temperature Coefficient” devices (NTC devices):
- PTC devices are devices whose resistance increases as their temperature increases.
- NTC devices are devices whose resistance decreases as their temperature increases.
Two types of temperature monitor channels are addressed herein, referring to the two main classes of transducers available on the market:
- TSM1: Wide range resistance acquisition, suitable for NTC thermistors (negative temperature characteristic).
- TSM2: Limited range resistance acquisition, suitable for platinum (PT) type.
The conditioning configuration to be used depends on the transducer used. Both TSM1 and TSM2 interfaces are specified in terms of resistance measurement accuracy. Note that TSM1 can be used for platinum type sensors (PT), but that generally shows worse accuracy than a well adapted TSM2. Also, TSM2 can be used for NTC type of sensor, but the temperature range is then restricted.
Last update: 21 March 2012