Hi, has anyone done a mega cheap 20MHz oscillator
to interface to a PIC?

In this situation I need about 20MHz for the
processing speed, but accuracy and drift etc are
not important. Anything that keeps to about 20MHz
+/-10% will be ok.

So far I have considered a 7414 hex schmidt
inverter as a 20MHz RC osc, fed into the PIC pin.
7414 about 5 cents or less and RC is < 1c.

But the PIC crystal osc itself is very close to
an inverter osc anyway, and should drive some
external components to 20MHz.

If anyone has replaced a ceramic resonator or
crystal with some network of capacitors/resistors
that would be excellent, and should be technically
possible driven from a PIC osc in HS mode.

What would be REALLY fancy would be a capacitor
circuit etched as part of the PCB to save the
cost of 0805 caps...

Nicer still if Microchip offered 20MHz PICs with
a 20MHz internal RC option, but I guess we'll be
waiting a while for that one.
:o)
-Roman

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