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TCA9543A: Can we connect multiple master?

supreeth sb
Prodigy 20 points
Part Number: TCA9543A

Hi,

I am trying to share two I2C slaves with two masters using TCA9543A as shown below. My doubt is that once we put first TCA9543A device in RESET state, will it release the slave I2C bus so that the second TCA9543A will be able to access the shared I2C bus or will there be any bus congestion. 

Kindly let me know if any additional information is required.

  • 0
    TI__Mastermind 47895 points

    Hi Supreeth,

    I don't see an issue using TCA9543A's reset pin to manage multiple masters in this way. This reset will set the device registers to their default state with all channels disabled so the inactive master will not be able to communicate with the downstream I2C lines. 

    I do recommend including a method to pull down the reset pins when the switch has left a device inactive. This may be a weak pull-down resistor included on both reset lines. Though this pin will passively fall to a ground potential, the high input impedance of the pin may make this process slow enough that it would impact communication during a switch. 

    Let m know if you have any other questions.
    Regards,
    Eric

  • 0 in reply to Eric Schott1
    Prodigy 20 points

    Thanks a lot Eric,

    That clears my doubt ... :)