ADuM3160 configuration

Hi everbody,I'm using adum3160 for isolate the PC and controller board, iCoupler ADuM4160/ADuM3160 USB Isolator Evaluation Board as reference, it's many confused about the PIN, configurated as high level but without response,no much better if LOW.

configuration arguments:

upstream------

VBUS1 : 5V

GND1: PC GND

VDD1: 3.31V

PDEN: 3.31V(connect with VDD1 directly)

SPU: 3.31V(connect with VDD1 directly)

D+,D-, always low.

downstream-------

VBUS2 : 3.3V

GND2: Board GND

VDD2: 3.3V(connect with VBUS2 directly)

SPD: 3.3V(connect with VBUS2 directly)

PIN: 3.3V(connect with VBUS2 directly)

D+,D-, always low.

I'm confused about PC with no response if pull up PIN, and I found that D+(upstream) pulled up to 1.5V if SPD configurate as LOW and SPU configurate as HIGH. it not allowed...

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  • 0
    •  Analog Employees 
    on Feb 2, 2012 6:56 PM

    Hello Jie,

    The PIN function allows the pullup to be applied to the upstream port under the users control.  The SPU pin will determine which upstrealm line the pull-up is applied to, as well as the buffers timing characteristics.

    Your summary of the voltages, (thank you, that helps a lot), says you are configuring this part to be Full speed so the D+ line should be pulled high to the Idle J condition when there is not active communication by the pullup.  Since this line is sitting at 1.5V, I would look for somthing loading down the line.  If the line is not pulled high, then it probably looks like D+ and D- are both low, which the PC will interpret as an open cable and enumeration will not start.

    For Full speed operation SPU, SPD and PIN should all be ~3.3V, and D+ should be pulled close to 3.3V.

    Are these voltages measured with the ADuM4160 connected to a host port, or is this for an open connector?  Does the USB port on the PC work properly when the ADuM4160 is not used?  How are you powering the downstream side of the ADuM4160?

    Best Regards,

    MSCantrell

Reply
  • 0
    •  Analog Employees 
    on Feb 2, 2012 6:56 PM

    Hello Jie,

    The PIN function allows the pullup to be applied to the upstream port under the users control.  The SPU pin will determine which upstrealm line the pull-up is applied to, as well as the buffers timing characteristics.

    Your summary of the voltages, (thank you, that helps a lot), says you are configuring this part to be Full speed so the D+ line should be pulled high to the Idle J condition when there is not active communication by the pullup.  Since this line is sitting at 1.5V, I would look for somthing loading down the line.  If the line is not pulled high, then it probably looks like D+ and D- are both low, which the PC will interpret as an open cable and enumeration will not start.

    For Full speed operation SPU, SPD and PIN should all be ~3.3V, and D+ should be pulled close to 3.3V.

    Are these voltages measured with the ADuM4160 connected to a host port, or is this for an open connector?  Does the USB port on the PC work properly when the ADuM4160 is not used?  How are you powering the downstream side of the ADuM4160?

    Best Regards,

    MSCantrell

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