Part Number:INA332
I'm working on a design for a load cell amplifier and am having trouble with the INA332 that I'm using to amplify the signal. After reading through the datasheet, I've ended up with the circuit below:
The gain is set at G = 5 + 5*(R2/R1) = 955 which is near the maximum for the INA332. I am getting a response when loading the strain gauges that corresponds to the load I'm putting on it.
The problem is that the output voltage is ~1.89V when (Vin+) - (Vin-) = 0.3 mV. Measuring Vin+ and Vin- referenced to ground show that they are ~1.5V. Am I missing something here? I connected REF to GND so that the output voltage would cover most of the range of the ADC when the gauge is loaded. 0.3 mV * 955 = 0.29V which made me wonder if I had a faulty connection on the REF pin. I measured the voltage at the pin and it is 0V.
Would anybody be able to tell me A) What I'm missing in the datasheet or B) What might be going wrong in my circuit?
Much appreciated,
Kevin