[sdiy] CMOS as voltage variable resistor

[René Schmitz]

Hi everyone!

At 00:34 01.05.02 +0000, Happy Harry wrote:
>The only way to use these as variable resistors is to chop them
>(PWM)...

One interesting possibility is to use a switched cap as a variable resistor. 
Frequency controlled, instead of pulsewidth control. I've recently used those 
to make a voltage controllable three phase LFO. Works nice, although its a 
sampling system. I'll be building a VC-ADSR with these.

>The 4007 has 'some' hopes a a variable resistance device... the
>4016 / 4066 ... very little (no) hope.

I see this the same way.

Cheers,
 René


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uzs159 at uni-bonn.de
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