# How to create a "Reverse polarized circuit" using analog circuit?

#### achen

Joined Sep 11, 2022
18
What I mean about "Reverse polarized circuit" is that it can take the input voltage and reverse it taking the 0 as axis of symmetry.

I want to realize it using analog circuitry like MOSFETs or OP Amp. it has to be working from -1.8V to 1.8V range at least.

#### Papabravo

Joined Feb 24, 2006
21,264
It is just an operational amplifier in an inverting configuration with a gain of -1. Like this:

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#### crutschow

Joined Mar 14, 2008
34,700
You will need two power supplies, one at least 2V plus and one at least 2V minus to power the op amp.
Do you have that?

#### Papabravo

Joined Feb 24, 2006
21,264
You will need two power supplies, one at least 2V plus and one at least 2V minus to power the op amp.
Do you have that?
I thought the supplies were ±1.8V and the signal was ±1.0V. At least that is what the signal graph seemed to imply.

#### crutschow

Joined Mar 14, 2008
34,700
Well the TS stated:
it has to be working from -1.8V to 1.8V range at least.
so I thought that meant the signal was up to 1.8V peak.

#### Papabravo

Joined Feb 24, 2006
21,264
Well the TS stated:so I thought that meant the signal was up to 1.8V peak.
He did include a diagram that shows a triangle waveform going from -1V to +1V. There is no problem making the waveform go ±1.8V as long as the opamp supply has sufficient head room to allow the output to make it all the way there, which would be the case with some headroom, if the supply voltages were ±2V as you suggested.

I have a prediction that we will hear no more from the TS on this thread since that seems to be what he does.