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Visitor II
March 22, 2011
Question

Maximum Cable length for I2C protocol in STM8S

  • March 22, 2011
  • 2 replies
  • 1181 views
Posted on March 22, 2011 at 08:21

Maximum Cable length for I2C protocol in STM8S

#i2c
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    2 replies

    Super User
    May 17, 2011
    Posted on May 17, 2011 at 15:12

    I2C has no specific limit on cable length as such, but there is a limit on total capacitance.

     

    Clearly, for any given cable type, this will limit the length of that particular cable.

    This has nothing to do with the STM8; it is defined in the I2C specifications - available from NXP:

    http://www.nxp.com/acrobat/usermanuals/UM10204_3.pdf

    Bus ''Repeater'', ''Hub'', and ''Extender'' chips are available for making ''long'' and/or complex I2C busses...

    http://ics.nxp.com/support/i2c.usage/

    http://ics.nxp.com/support/interface/

    Visitor II
    May 17, 2011
    Posted on May 17, 2011 at 15:12

    neil.andrew

    Thanks for your reply. It seems there are several factors which are to be considered for I2C cable length like frequency(lower the better for long lengths), capacitance the following link is also pertinent to the topic

    www.nxp.com/documents/application_note/AN10658.pdf