Gerhard Fiedler wrote:
>
> At 20:03 19/05/97 +0300, Jussi Vainionp 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?
> >
> >I'll try to reproduce a part of the schematic here:
> >
> >[...]
> >
> >I don't quite understand what those S1 and S2 things are.
>
> Those S1..S4 are the 4066, as you said a quad analog switch. The numbers in
> the circles should be the control inputs, and the other two the pins for
> signal i/o. U1 seems to be an opamp (of your choice), _not_ the 4066
> (despite the number being very close to it...).
>
> If you want to make some experiments with this circuit, I'd be interested
> in the results, and willing to help you with the analog part of it :-)

Why not charge a cap and measure time-to-trip on an input? You only
need a cap and two resistors.

--
Friendly Regards

Tjaart van der Walt
mailto:tjaart@wasp.co.za
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