Capacitor Voltage Divider

[Yoa01]

Hi all,

Just a quick question for you: is it at all possible to use a capacitor voltage divider with DC voltages? I know, somewhat stupid question given that caps tend to remove DC offset and thus the output would always be pretty much 0V, but I am wondering if there is some kind of known circuitry that allows DC voltages to be divided by such a capacitor.

For those wondering why I want to do this, or why I can't use a simple resistor voltage divider: I want to build a theremin controller for an analogue synth. Theremins work by using your body and the metal rod as a capacitor.

The best I've got is I could run a signal, like a sine wave, to the first cap in a series of two, use the divider as an attenuator, then use a setup of diodes and regulators on the output (between the caps) to end up with positive and negative (or just positive, I can invert the signal) DC outputs. I have no idea if that would even work, let alone how well it would work.

What I really want is the ability to use a theremin-like setup as a way to control an output capable of voltage sweeps from +5V to -5V. Any advice is appreciated.

 

[(*steve*)]

is it at all possible to use a capacitor voltage divider with DC voltages?

No

OK, strictly the answer is "yes", but it won't work.

What I really want is the ability to use a theremin-like setup as a way to control an output capable of voltage sweeps from +5V to -5V. Any advice is appreciated.

Build so much of a theremin that is necessary to provide the functionality you desire.

 

[Yoa01]

Build so much of a theremin that is necessary to provide the functionality you desire.

I've yet to find any theremin designs that utilise a vco fed by a voltage created using the antenna, sadly. Maybe I could make a simple theremin and use a kind of audio-to-voltage converter...