At 12:54 PM 6/11/2003 -0400, you wrote:
>You'll have to build your own clock oscillator.  Do a search on Google
>for crystal oscillator circuits and you should come up with something.
>The on-chip crystal oscillator is not intended to directly drive a 40MHz
>crystal.

The easiest thing would be to buy a 40MHz oscillator, such as the
ECS 8FM-400. About 3 bucks in small quantity. They draw a lot of supply
current, beware if that's important to you.

>It may be tricky getting a circuit to drive a 3rd overtone crystal,
>though.  Good luck!

You have to add a tuned circuit so it doesn't oscillate in the fundamental
mode (13.333 MHz).

Best regards,

Spehro Pefhany --"it's the network..."            "The Journey is the reward"
speff@interlog.com             Info for manufacturers: http://www.trexon.com
Embedded software/hardware/analog  Info for designers:  http://www.speff.com

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