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Old 09-05-2013, 02:11 PM
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MITCH electronics MITCH electronics is offline
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Default PIC18f45k20 maximum clock speed

Hi everyone,

I noticed that the largest internal oscillator speed is 64Mhz (if you use PLL) but what im trying to figure out is what is the maximum clock speed if you use an external clock? Is it 64Mhz (like the internal oscillator) or can I go higher? Im having a tough time finding this on the datasheet. Any help is much appreciated

All the best,
Robin
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Old 09-05-2013, 02:16 PM
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Hello,

On this page Microchip states "Two external clock modes up to 64 MHz".
http://www.microchip.com/wwwproducts...cName=en026337

Bertus
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Old 09-05-2013, 02:16 PM
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per the features it says
"Two external clock modes up to 64 MHz"
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Old 09-05-2013, 02:17 PM
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Fantastic!

But here is a question, is this 64 before PLL or after PLL???
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Old 09-05-2013, 04:11 PM
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its 64 MAX...
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Old 09-05-2013, 05:41 PM
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Awww
But can I? NO
But what if I..? NO

Ok
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Old 09-07-2013, 06:51 AM
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Try it if you like. I remember in the old days people were running PICs at far above the "max" speed, as much as four times over.

It will depend on how much you try to bump the speed, how cool you can keep the chip and what failure rate you can tolerate.
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