> I have successfully overclocked a 20Mhz 16C73 to 57Mhz.  It could
> possibly run faster, but that was the fastest can oscillator I could find
> at the time.  VCC was 5.01 V and the chip ran cool.
>
> My guess is that if you always ran the chips at near the high end of the
> VCC range (5 V and above) you could get them to run at least double
> their rated speed.
>
>

>
> > Peter Forde wrote:
> > >
> > >   As a matter of curiosity, how fast can you overclock a PIC with
> > > injecting an external clock signal?
> > >
> > >   I'm experimenting with PIC16F877-04/P, and been injecting into CLKIN
> > > from an EXO 16MHz clock generator.  Usually use the 4 MHz divided output
> > > from this but sometimes I select the 16 MHz output, when the PIC still
> > > seems to work perfectly well.  Doesn't get warm or anything.
> >

This was covered extensively previously on the PICLIST and I seem
to recall that yes you can overclock PICs, some found that their
max freq was quite high like the 57 MHz from a 20MHz PIC that
Charles found BUT also some frequencies BELOW that max would
not work.
Basically a pretty dodgy arrangement, fun to play with but it will
probably bite you on the ass if you go to production quantities.

_____________________________

Lance Allen
Technical Officer
Uni of Auckland
Psych Dept
New Zealand

www.psych.auckland.ac.nz

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