#### AMSA84

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Hi guys, I am simulating a open-loop comparator with positive feedback (it is not the dynamics one).

What happens is that, I simulate the dc-characteristic and ask for the derivative of the characteristic to see where the max is. The value that he gives me is supposed to be the gain, right?

Supposing that it is the gain, there is something that is confusing me.

When I simulate for example, between a range of input voltage varying, say 1.6V to 1.7V with a step of 1mV the "gain" is around 3K. When I simulate the same thing, but now with a step of 0.1mV the gain gives higher, around 30K.

When I set a very small voltage sweep rang, say 1.6485V to 1.6515V with 100nV of step, it gives me 128K of gain.

Hows that possible?

- - - Updated - - -

I forgot to ask another thing. This gain is the dc gain, right? What about the gain from the frequency response of the comparator? VDC source in vin+ in series with a vsin VAC=1 and other VDC source at the vin- pin with the polarization voltages. What kind of gain is this? If I want to know the bandwidth of the comparator, this is one way to do it, right? But what about the gain that we get? What's his name?

Regards.

What happens is that, I simulate the dc-characteristic and ask for the derivative of the characteristic to see where the max is. The value that he gives me is supposed to be the gain, right?

Supposing that it is the gain, there is something that is confusing me.

When I simulate for example, between a range of input voltage varying, say 1.6V to 1.7V with a step of 1mV the "gain" is around 3K. When I simulate the same thing, but now with a step of 0.1mV the gain gives higher, around 30K.

When I set a very small voltage sweep rang, say 1.6485V to 1.6515V with 100nV of step, it gives me 128K of gain.

Hows that possible?

- - - Updated - - -

I forgot to ask another thing. This gain is the dc gain, right? What about the gain from the frequency response of the comparator? VDC source in vin+ in series with a vsin VAC=1 and other VDC source at the vin- pin with the polarization voltages. What kind of gain is this? If I want to know the bandwidth of the comparator, this is one way to do it, right? But what about the gain that we get? What's his name?

Regards.

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