Is pin1 and pin2 virtually shorted, pin3 and pin4 virtually shorted?

Hi howardaaa ,

Yes, the pins of A1 and A2 can be analyzed by using virtual shorts. However, other components around the inputs of A1 and A2 such as the current source and voltage source could affect the analysis. Regarding your last question, I would not recommend using such a method; instead, you can use two separate op-amps to see the result. May I know why you want to check the signal around these pins?

Regards,
Gilbeys

It's just that my customer need another signal conditioning circuit to condition Sensor+ vs Sensor-, and the input impedance is low compared to Sensor output impedance, if we connect it to PIN2 and PIN3, instead of PIN1 and PIN4 of AD8220, we guess the low input impedance is not a problem, but if we connect it directly to PIN2 and PIN3, the high output impedance of the sensor will cause problem (the actual voltage seen by the signal conditioning circuit is lower than actual voltage).

Hi howardaaa ,

Good day. Sorry for missing the thread. Can you email me the specifications of what the customer wants for their system? Thank you.

Regards,
Gilbeys