VCDO

[jbv]

Don Tillman :

> Yeah, this was discussed not too long ago.  Here's my contribution:
>

(SNIP)

> But Magnus' suggestion got me thinking... you could also but together
> something with a regular audio-range sawtooth VCO, a counter connected
> to a DAC, and a comparator circuit.  The sawtooth reset pulse zeros
> the counter, and as the sawtooth ramps up you compare the sawtooth
> voltage with the DAC output, when the sawtooth voltage is delta-V
> above the DAC you clock the counter.  Pretty clean, and you get a
> simultaneous analog sawtooth.

Hey, I like the idea ! Has anyone tried to implement that ?

How would you reset the counter when the sawtooth goes low ? Using another
comparator ?
It seems that the sawtooth signal should be pretty stable (in terms of
amplitude), in order to
ensure a steady number of steps when it ramps up, otherwise the counter might
produce
different counts for each period  - or perhaps would it be percieved as a "nice
analog touch
distortion" ? ;-)
And what about precision calibration of the whole thing ?

jbv