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Thread: delay of nanosecond Teensy ?

  1. #1
    Junior Member
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    Apr 2019
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    delay of nanosecond Teensy ?

    is it so possible to make a delay of nanosecond between a low and high state with a teensy 3.6 seen that its frequency 180 MHZ ?

  2. #2
    Senior Member
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    Jul 2020
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    I don't think the pin drivers can go that fast even if given a 500MHz signal... Typical external CMOS pins have rise- and fall- times of a few ns.
    For faster you need impedance matched LVDS or similar - this is into the microwave frequency domain, everything needs to be a transmission
    line.

  3. #3
    Junior Member
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    experimentally with the microsecond delay function I can go down to 7 microseconds after remaining constant!

  4. #4
    Senior Member PaulStoffregen's Avatar
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    Nov 2012
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    Here's a thread about fast I/O on Teensy 3.6 which might help. In particular, look for the info about disabling slew rate limiting (which normally you would want, as it greatly reduces high frequency noise & other undesirable effects).

    https://forum.pjrc.com/threads/41874...l=1#post132347

    And here is similar info for Teensy 4

    https://forum.pjrc.com/threads/57185...l=1#post212236

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