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Zener Diodes

Discussion in 'Electronic Projects Design/Ideas/Reviews' started by AtomSoft, Nov 25, 2014.

  1. AtomSoft

    AtomSoft Well-Known Member

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    Can i use a Zener on a data line? What would be better...

    I want to drop some SPI lines down to 3.3v (3.6v max) can i use zeners to simply drop the voltage of a HIGH ? and Low being low already...

    Or is using a BUFFER a MUST... which is better and why?
     
  2. 4pyros

    4pyros Well-Known Member Most Helpful Member

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  3. MikeMl

    MikeMl Well-Known Member Most Helpful Member

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    A Zener clamp at the listener input requires a resistance in series with the data line between the sender and the listener. That will slow down the signalling a bit. Does that matter? It might, depending on the data rates.
     
    • Agree Agree x 1
  4. dave

    Dave New Member

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  5. Ian Rogers

    Ian Rogers Super Moderator Most Helpful Member

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    I always use a potential divider... The last SPI module ( TFT screen ) I used, was running at 8Mhz + no problem..
     
  6. Cicero

    Cicero Active Member

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    Yeah, I'd use a potential divider, or level shifters. Zeners require a decent amount of current, and it'll load your SPI bus.
     

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