ee484
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Hi, all.
I'm currently testing a opamp with unity gain feedback.
With small DC input (<30mV), it seems that it does not have any problem.
However, as DC input increases, the output of the opamp (unity gain feedback) has oscillation and it is proportional to the input amplitude.
Since it does oscillate with DC input, I don't think it comes from lack of phase margin..
What's the typicall senario that cause this oscillation in a testing? The oscillation frequency is about 1.2MHz.
If I put 1MHz cutoff freq. low pass filter, it does it's job.
Thanks...
Best.
B
I'm currently testing a opamp with unity gain feedback.
With small DC input (<30mV), it seems that it does not have any problem.
However, as DC input increases, the output of the opamp (unity gain feedback) has oscillation and it is proportional to the input amplitude.
Since it does oscillate with DC input, I don't think it comes from lack of phase margin..
What's the typicall senario that cause this oscillation in a testing? The oscillation frequency is about 1.2MHz.
If I put 1MHz cutoff freq. low pass filter, it does it's job.
Thanks...
Best.
B