In Reply to: Re: Isn't Slew Rate a bit like THD? posted by john curl on July 22, 2003 at 23:11:53:
Hi,>Therefore, if you have an open loop bandwidth (dominant pole) of
>1MHz, then you won't have any TIM distortion below 1MHz. However,
>you can have plenty of harmonic distortion that is frequency
>sensitive, due to non-linear cap effects. Is this making sense to
>you?I thought part of TIM's cause was due to non-linear cap effects...
OK. I could be way off on attributing the effect of the square
wave to TIM. In the papers I've read so far, I haven't come across
anything about TIM not appearing below the dominant pole. If you
know of a reference, that would be well appreciated.Back to non-linear cap effects...this is one difference between
a simple emitter follower and a Sziklai. The Sziklai is more
sensitive to this effect and produces more distortion (see sims
in transient test thread). I had to increase the peak voltage on
the Square wave from 4 to 8 volts in order to see it while leaving
the sine wave at 1v peak.>TIM is an op-amp dominated kind of distortion
Since amps don't have these low frequency open loop dominant poles,
and opamps do, then it sounds like TIM isn't much of a problem to an
amp?
This post is made possible by the generous support of people like you and our sponsors:
Follow Ups
- Re: Isn't Slew Rate a bit like THD? - mfc 23:53:20 07/22/03 (2)
- Re: Isn't Slew Rate a bit like THD? - Scott Frankland 01:44:23 07/23/03 (1)
- Re: Isn't Slew Rate a bit like THD? - john curl 08:02:11 07/23/03 (0)