Approach to select the correct switch

Discussion in 'General Electronics Chat' started by Andrey Mazur, Jul 1, 2016.

  1. Andrey Mazur

    Thread Starter New Member

    Jul 1, 2016
    2
    0
    Hello guys,

    I am developing a bridge device between two other devices(suppose Dev #1(master) and #2(slave)) and now I am stacked with the following problem:

    My bridge has 2 USB connectors, USB-A plug and USB-B plug. The master device is connected over the special connector, over this connector 2,2V and !POWER_EN are devilered to the bridge. And it is necessary to make a switch between two USB plugs and these two signals in that way that only in the case when these two pins are high to allow the voltage flowing from A to B. I have drawn and attached the primitive logical scheme how I see this should work. To make AND and OR I have to transistors to build logic gates, but switch is a big problem, because a switch has 2 lines only, so how to connect the third one?
     
  2. ElectronicMotor

    Member

    May 1, 2016
    53
    6
    USB communication can be very temperamental. If you switch the two twisted wires (twisted pair), you will probably have to follow the bandwidth specifications very closely.

    At high speed, electrical signals tend to jump out of the wire.
     
  3. Andrey Mazur

    Thread Starter New Member

    Jul 1, 2016
    2
    0
    The thing is that from USB I need only Vcc, data is not interesting, USB is only for power supplying, so I think that 74AHC1G08DBV component can be used as the and gate and TPS22918 as a voltage switch, what do you think about this choise?

    Thanks
     
Loading...