 #1
FOIWATER
Gold Member
 434
 12
Main Question or Discussion Point
In the following diff amp, only one output is taken from collector two.
When I calculate the differential mode gain using the second differential input (Vid/2) I get a positive gain. When I calculate the differential mode gain using the first differential input (Vid/2) I get a negative gain.
A spice simulation of this circuit shows that the output is positive.
I would then expect to get a negative gain for (vid/2) and a positve gain for (vid/2)
Does someone know why that is not the case?
When I calculate the differential mode gain using the second differential input (Vid/2) I get a positive gain. When I calculate the differential mode gain using the first differential input (Vid/2) I get a negative gain.
A spice simulation of this circuit shows that the output is positive.
I would then expect to get a negative gain for (vid/2) and a positve gain for (vid/2)
Does someone know why that is not the case?
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