ren_zokuken01
New Member
I've always thought that a Non-inverting configured Opamp simply takes the AC part of a signal and leaves out the DC, hence only needing for a +/-. Then reproduces the AC (with gain) and leaves out the DC. So the signals don't even have to be on the same ground as the supply voltage of the Opamps. The input can be from a completely different powered supply and it can be reproduced at by the Opamp as signals (with gain) much, much lower peak to peak Voltage range. So that's isolation, right? No common grounding needed.
Transformers also work the same way. Albeit the amplitude average of the input will be the average ground of the output, so not the same type of isolation as with Opamps. Also, Gyrators (active component Inductors), can be implemented by Opamps.
So why can't I reverse the inputs of the Opamp (while keeping the Non-inverting configuration) and expect that it will produce an inverted output? Is the positive input strictly only for push and the negative only pull, dictated by the fact that they are made out of transistor which needs proper biasing?
So are Opamps only like a transformer for only half (positive or negative) of an AC signal?
Transformers also work the same way. Albeit the amplitude average of the input will be the average ground of the output, so not the same type of isolation as with Opamps. Also, Gyrators (active component Inductors), can be implemented by Opamps.
So why can't I reverse the inputs of the Opamp (while keeping the Non-inverting configuration) and expect that it will produce an inverted output? Is the positive input strictly only for push and the negative only pull, dictated by the fact that they are made out of transistor which needs proper biasing?
So are Opamps only like a transformer for only half (positive or negative) of an AC signal?
Last edited: