A
Amanda Robin
- Jan 1, 1970
- 0
Hello all,
I am reviewing my old electronics notes in preparation for a
comprehensive exam.
In my notes I have written, a couple of times, that with a non-inverting
op amp configuration there is common mode voltage, and with an inverting
configuration there is no common mode voltage.
I know the definition of common mode voltage, but I look and look at the
circuit diagrams and can't see why one would have it and the other not.
One of the basic "rules" for op amps is that both input terminals are
ideally held to the equivalent voltage. So it seems to me that every op
amp in the world, however configured, would ideally have common mode
voltage. (I'm probably confusing two different things here, but maybe
someone can help me get unconfused.)
Is it because, with the inverting configuration, the input terminals are
held to ground? And zero V on two terminals doesn't count as common?
Thanks for any tips.
Amanda
I am reviewing my old electronics notes in preparation for a
comprehensive exam.
In my notes I have written, a couple of times, that with a non-inverting
op amp configuration there is common mode voltage, and with an inverting
configuration there is no common mode voltage.
I know the definition of common mode voltage, but I look and look at the
circuit diagrams and can't see why one would have it and the other not.
One of the basic "rules" for op amps is that both input terminals are
ideally held to the equivalent voltage. So it seems to me that every op
amp in the world, however configured, would ideally have common mode
voltage. (I'm probably confusing two different things here, but maybe
someone can help me get unconfused.)
Is it because, with the inverting configuration, the input terminals are
held to ground? And zero V on two terminals doesn't count as common?
Thanks for any tips.
Amanda