On Jan 7, 2009, at 8:26 PM, Monroe Eskew wrote:

> Specifically, what is the
> mechanism for converting sawtooth to square, or triangle to square
> And what is the mechanism for PWM

A circuit called a comparator is used. Basically a comparator is a
circuit with two inputs, which goes high when the voltage in one of
its inputs is above the other reference voltage.

As an example, if a wave like a 0-10v triangle or saw is put into one
input of a comparator and the reference input is set to 5v, the result
will be a square wave.

To achieve PWM, the reference voltage is also an input, typically
coming from something like an LFO.

- C

Chris Muir
cbm@...
http://www.xfade.com