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Maximum I/O Pin voltage? — Parallax Forums

Maximum I/O Pin voltage?

ArchiverArchiver Posts: 46,084
edited 2002-10-01 06:16 in General Discussion
I know this must be in the Stamp Manual somewhere, I have looked up other
electrical specs before...but I can't find it now!

What is the maximum input voltage to an I/O Pin?

Thanks in advance,

Neil

Comments

  • ArchiverArchiver Posts: 46,084
    edited 2002-10-01 03:09
    At 01:35 AM 10/1/02 +0000, capthoohoo wrote:
    >I know this must be in the Stamp Manual somewhere, I have looked up other
    >electrical specs before...but I can't find it now!
    >
    >What is the maximum input voltage to an I/O Pin?

    Allowable range is 0V thru 5V. Hard limits that still allow valid
    operation are -0.3 thru +5.3V. Letting out smoke limits are voltages less
    than -0.6V or greater than +5.6V.

    dwayne

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  • ArchiverArchiver Posts: 46,084
    edited 2002-10-01 03:23
    At 01:35 AM 10/1/02 +0000, you wrote:
    >I know this must be in the Stamp Manual somewhere, I have looked up other
    >electrical specs before...but I can't find it now!
    >
    >What is the maximum input voltage to an I/O Pin?
    >
    >Thanks in advance,
    >
    >Neil


    Technically the protection diodes won't let you take the I/O's above 5.6V
    with a 5V source
    without passing current through the protection diodes, which by the way are
    not meant to
    handle excessive currents, so it is best to keep your input voltages at or
    below 5V.

    Protection Diodes:

    VDD >
    |<----o----|<
    <VSS
    |
    |
    I/O


    I'm not sure about the newer BS2's, but with the original BS2, it actually has
    a PIC16C57C-20/SS. Looking at the specs for the PIC16C5X on page 25 you can
    see the "equivalent circuit for a single I/O pin"... not shown are the
    protection
    diodes that go to VDD and VSS. Look at page 61 for electrical specifications.


    http://www.microchip.ru/cdrom/download/lit/pline/picmicro/families/16c5x/devices\
    /16c57c/30453c.pdf


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  • ArchiverArchiver Posts: 46,084
    edited 2002-10-01 06:15
    <PRE>unsubscribe --please
  • ArchiverArchiver Posts: 46,084
    edited 2002-10-01 06:16
    <PRE>unsbscribe me --please
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