At 08:03 PM 5/19/97 +0300, you wrote:
>Microchip application note AN513 describes a method for ADC.
>I'm not that great at analog electronics, and I don't quite understand the
>schematics. It has this chip that is supposed to be voltage to current
>converter 4066, but according to my data it is a quad bilateral analog
>switch. How could it convert anything?

It uses an op-amp they don't specify. You can use a 741 or LF353, et.
But by then, you may be better off with a seperate A/D. I've also found that
they linearity of quad bilateral switches (analog mosfet muxes too) vary
greatly, and as critical in this application. An ugly can of worms, for sure.