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TPD3S714-Q1: Can the IC be used for Signal-switching?

Tim Riese
Prodigy 100 points
Part Number: TPD3S714-Q1

Hello,

can this Part be used to reliably used to switch the Datalines via the !EN Pin?
Or is there a problem regarding USB-OTG Support, where the Datalines remain active after disabling the IC?

Thanks for the Help,

Tim 

  • 0
    TI__Mastermind 32661 points
    Tim,

    As long as the system properly handles the VBUS signaling, the Enable pin can be used to disable the D+/D- switches.

    The issue that I see with the system is that there will be two ICs and two ESD protection devices present on the D+/D- lines which will make passing the RF compliance for USB very difficult.
  • 0 in reply to Chuck Branch
    Prodigy 100 points
    Maybe i explained my Problem a little bit to inexplicit. I have two of these ICs more or less in series to switch the Bus.
    Your concern with the ESD can be solved if i only use ESD Protection for one time.

    Therefore it should be no Problem to switch the signals using the !EN pin. I had the otg problem with another chip
    because it had the feature to leave the Data lines connected when the IC is disabled. But that shouldnt be the case with the IT chip
    like you mentioned.
  • 0 in reply to Tim Riese
    TI__Mastermind 32661 points
    Tim,

    The TPD3S714 disables the switch for the D+/D- when the device is disabled. This will disconnect it from the bus, but it does not reduce it's output capacitance, so you will have to be careful to ensure that the down stream host/hub/device is able to detect a disconnect and that you meet the eye diagram requirements for the series connection.

    If you meet those two requirements, then I think you will have a functioning system.

    Regards,
    Chuck
  • 0 in reply to Chuck Branch
    Prodigy 100 points

    Hello Chuck,

    i observed the behaviour you described where the Signal passes through the disabled chip.

    Is there any way or IC-Solution where i can reliably switch of datalines without any coupling?
    For axample a switch which either routes the signal through or onto an 45 Ohm resistor to reduce any reflections. 

    Regards,

    Tim