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#Post#: 9--------------------------------------------------
Schoolboy Error!
DIR By: MC12
Date: February 13, 2021, 5:09 am
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I have been doing my nut the last several days trying to figure
out what I was doing wrong, why an op-amp circuit won't
simulate. Here it is (an extracted element from a larger
circuit, for the exercise of figuring out the problem):
[attach=1]
...which, when simulated in transient mode with a 5kHz input
stimulus from V1 produces a flat line on OUT:
[attach=2]
And yet, if I remove the HF suppression capacitors, it works
fine:
[attach=3]
Just for a bit of suspense, I'll give the answer in a later post
if nobody gets it (and it really is a schoolboy error!)
#Post#: 79--------------------------------------------------
Re: Schoolboy Error!
DIR By: MC12
Date: February 10, 2025, 3:13 am
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A recent post has reminded me I never got around posting the
solution:
The capacitors in the circuit are given values "220". That's in
Farads! 220p is the desired value.
#Post#: 80--------------------------------------------------
Re: Schoolboy Error!
DIR By: Robert
Date: February 11, 2025, 11:14 am
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The source V1 is floating. - No error message?!
#Post#: 82--------------------------------------------------
Re: Schoolboy Error!
DIR By: MC12
Date: February 11, 2025, 5:23 pm
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--- Quote from: Robert link ---
>
> The source V1 is floating. - No error message?!
>
--- End Quote ---
I don't recall there being an error, but in any case it isn't
floating. V1 is applied across a differential input with DC
path to GND.
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