ODP: Radio scan controller?

[Roman Sowa]

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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when 1st one is on, the other is off, and vice versa
the switches are controlled by clock signal
the other ends of switches can be seen as resistor terminals.
Changing clock frequency will change this circuit's resistance

this is widely used in filters, but since clock is often in 50:1 to 200:1
relation
to cutoff frequency it's not very usefull at low frequencies.

Roman

> -----Oryginalna wiadomość-----
> Od:	Plinio Andres Barraza [SMTP:pab210 at is8.nyu.edu]
> Wysłano:	6 listopada 1998 20:17
> Do:	Paul Perry
> DW:	synth-diy at mailhost.bpa.nl
> Temat:	Re: Radio scan controller?
> 
> I remember a while back a discussion about switched capacitors, someone
> mentioned they were on the way to being digital.  Are switched capacitors 
> devices that do the equivalent of laying down a series of capacitors of
> different values and just switching between them?     
>