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pic18lf frequency vs supply voltage.

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HOODEY
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2019/06/11 18:58:21 (permalink)
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pic18lf frequency vs supply voltage.

I would like to run my pic18lf4525 on 3.6v at 32mhz.
 
However at that voltage the data sheet says the maximum frequency should be 30mhz.
 
What are the consequences of trying to run at a higher freqency than stipulated?
#1

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    ric
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    Re: pic18lf frequency vs supply voltage. 2019/06/11 19:06:02 (permalink)
    +1 (1)
    It might not work correctly over the full temperature range.
    Also note, "mhz" != "MHz". Case matters in SI units.
     

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    mbrowning
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    Re: pic18lf frequency vs supply voltage. 2019/06/11 19:06:10 (permalink)
    +2 (2)
    First, there is no 32 millihertz setting.
    if you select 32MHz instead, for a hobby project the datasheet police will arrest you for speeding. For a professional project your boss will fire you.

    Oh well - there's always next year
    #3
    1and0
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    Re: pic18lf frequency vs supply voltage. 2019/06/11 19:08:46 (permalink)
    +1 (1)
    HOODEY
    What are the consequences of trying to run at a higher freqency than stipulated?

    You are out of spec. Do it at your own risk! ;)
     
    #4
    pcbbc
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    Re: pic18lf frequency vs supply voltage. 2019/06/11 19:24:12 (permalink)
    +2 (2)
    ric
    It might not work correctly over the full temperature range.

    Also due to minor variations in production, some chips may work while other may fail. So even if you test this with one device and it appears to work over a given temperature range, the next part you try may not...
    That means even if you “test” your out of spec operation there are absolutely no guarantees of anything.

    Basically you’d be crazy to try this in anything other than a hobby project you don’t give a flying flip about if it works reliably or not. If you absolutely require 32MHz @ 3.6V then choose a part where this is within spec.
    #5
    mpgmike
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    Re: pic18lf frequency vs supply voltage. 2019/06/12 09:03:02 (permalink)
    +1 (1)
    Is there any specific reason you couldn't use a newer PIC designed to work at that voltage & Fosc?  Heck, you might even be able to switch from EXTOSC to INTOSC with ease (and probably some other useful things like XLP).  I'll bet there are probably much more capable PICs at... dare I say, 1/2 the price.

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    HOODEY
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    Re: pic18lf frequency vs supply voltage. 2019/06/23 10:20:22 (permalink)
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    I dropped the frequency to 8mhz using internal oscillator and can now run pic18f or pic18lf .
    #7
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