Q
We use AD7792 for our RTD measurement system. Page 4 (REV A datashee) show
characteristics for "TEMPERATURE SENSOR". Could you please explain me what is
this about ? Does it means that the chip has got an embedded temperature sensor
? If yes how can we use it (no registers to read the sensor).
A
The AD7792 has an on-chip temperature sensor.
By setting the bits CH2 - CH0 to 110 respectively, the on-chip temp sensor is
connected to the sigma delta modulator.
When the bits are set as above, data from the temp sensor will be converted by
the ADC.
The temp sensor has good relative accuracy.
However, you need to calibrate the sensor so that the actual value read back
accurately reflects the actual temperature.
The registers are shown on page 18 of the Revision A datasheet.