cv controlled capacitance

[synth_ollie]

a cv input and an output wich capacitance is changed by the cv input

sort of a vactrol circuit but with a capacitance that is changed instead
of a resistance, as in a "normal" vactrol, if you see what I mean....

if is this is not too complicated, how do I do it ?

cheers

OLLIE

[elektro80]

United States Patent 5510755

[etaoin]

http://en.wikipedia.org/wiki/Varicap

[yusynth]

The capacitance variation of a varicap is smaller than 500pF which is not very useful for say designing VCF...

The alternative is to use a capacitance simulating circuit that uses two OPA. But if you wish to control the simulated capacitance with a CV, you would either need a vactrol or an OTA... Therefore, this is not a reasonable alternative, I think.

[etaoin]