ODP: switching caps prob

[Roman Sowa]

I think it has something to do with "current injections" caused
by the switches during switching. I've seen some designs, where
bottom lead of the cap was connected to gnd through two switches
running simultanously with main switches.
Then switches 'nonidealities' would cancel

Roman


> -----Oryginalna wiadomość-----
> Od:	Rob Brzykcy [SMTP:cyborg0 at globaleyes.net]
> Wysłano:	7 listopada 1998 18:10
> Do:	Roman Sowa
> DW:	synth-diy at mailhost.bpa.nl
> Temat:	switching caps prob
> 
> BTW, if you are switching capacitances in and out of a filter, make sure
> you
> switch them completely out, IOW, dont leave the disabled cap to ground cuz
> it
> will affect you circuit. Switch out BOTH leads of the cap if you want
> predictable results. I can't truly explain why, but I tried every
> configuration
> when I was trying to mess with cap values in a filter and I finally ended
> up
> switching both leads out and it worked fine only then.
> Rob
> 
> Roman Sowa wrote:
> 
> > Switched capacitors is a way of replacing a resistor and have the
> ability
> > to change its value.
> > A cap grounded at one end has two switches at the other end.
> >
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> >       ===
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>