On May 3, 2005 06:58 am, Jinx wrote:
> > I think the original spec was reasonably clear
> > Viz
> >
> > >I need a low frequency vco that draws very little power. ...
> > > I need something that will oscillate between 55 and 65 Khz. It
> > > has to draw microamps of supply current, and I prefer the control
> > > voltage range to be between 1 and 3 volts.
> >
> > The implication (to me anyway) is that he wants an oscillator which
> > is tuneable in a reasonably smooth manner between 55 & 65 KHz by a
> > 1 to 3 volt signal
>
> That might not necessarily have been the requirement. There was
> no mention of infinite (ie analogue) variability or even whether
> there were any steps between 55kHz and 65kHz, or over what time
> period. I didn't mean to sound snippy in my reply but you know
> how often we play 20 Questions
>
> Apart from the PIC and 40xx there may not be alternatives at
> that power level

He can look at the circuit used in a television, 55kHz to 65kHz is more 
or less the same speeds used for the horizontal trace on a television, 
and those circuits certainly need to "syncronize" to another signal.
All he needs to do is recalculate values so that his circuit uses 
miniscule amounts of current versus a regular horizontal trace.

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