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Thread: What is the frequency stability rating of the 24MHz crystal used on teensy4.0/1?

  1. #1
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    What is the frequency stability rating of the 24MHz crystal used on teensy4.0/1?

    I'm working on something that requires pretty minimal drift between multiple devices.
    I'm hoping I can pull it off with a Teensy4.
    Is there a part-number/manufacturer (or just a rating) for the 24MHz crystal used on
    these boards? Specifically, I need to know the PPM rating of the main crystal and
    whether or not it is consistent across boards (i.e. is a single manufacturer with a
    specified rating used?).
    Thanks,

  2. #2
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    Mine is off by about 9 ppm. If this is an audio application and you have a reference, you can tweak the rate to be exactly correct.

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    I won't have a reference, just standalone teensy4 (if possible), so I'm hoping I can get the manufacturer's rating.
    I can see "2400T E8YU2" on the crystal, but can't get any info from google on that...
    Thanks,

  4. #4
    Senior Member PaulS's Avatar
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    Looks very much like an EPSON FA2016AN series crystal, datasheet here.
    But only Paul Stoffregen can tell what the exact part# is that PJRC orders...

    Paul

  5. #5
    Senior Member PaulS's Avatar
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    Found a message from Paul Stoffregen, mentioning "That's well within the crystal's 30 ppm spec".

    Paul

  6. #6
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    Wow, thanks for digging (more effectively than I did)!

  7. #7
    Senior Member+ manitou's Avatar
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    FWIW, i have anecdotal data on crystal drift measured with GPS PPS on various T4s, see
    https://forum.pjrc.com/threads/54711...l=1#post195166
    your mileage may vary. of course, temperature and age can affect frequency drift.

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