I am using INA2332 with a single supply of 5V.
The input to the op amp is a thermocouple output in the range of 0 to 50mV. The gain is set to 20.
My circuit works fine when Vref is grounded or set to a value of 100mV .
I want to connect a voltage of 1V at the VRef pin, in this case there is no output.
Can you tell me what is the maximum Vref that i can use?
Is Vref in this device only for offset trimming?
Varsha
Varsha,
If your thermocouple is referenced to ground, then the input voltage will be outside the common mode range of the INA2332. Doing some simulations in TINA (sim file attached) I found that there was no reference voltage which would provide linear output for 0 to 50mV ground referenced input. One solution is to apply the 1V reference to both the reference pin and to one side of the thermocouple. This will increase the input common mode voltage to a range which allows for linear operation of the INA2332:
