Original question:
Hello,
I'm trying to simulate an INA333 circuit in TINA and it does not appear to be working.
My input sine wave is set a min/max of 0 - 13mV. The gain should be approx 92 according to the datasheet, per my gain resistor of 1.1k. As seen in the screenshot below, the output is not as expected (should be a sine wave with min/max 0 - 1.96V offset by 200mV.
What am I doing wrong?
Thanks!
Hi Wilson,
you have violated the common-mode input voltage range of INA333. Stay at least 0.1V away from the supply rails:
So, your signal is already wrong at the output of INA333.
Kai
Hi Wilson,
if you cannot change the input voltage (6.5mV +/- 6.5mV), then you urgently need to use a negative supply voltage. If you take -2V as negative supply voltage and +3V as positive supply voltage, you can get the following results:
But if you choose 0V as negative supply voltage, your circuit will not work with your input signal:
You could use the negative bias generator LM7705 to produce -0.23V. But you would additionally need to reduce the gain then:
Kai
