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DP83848VYB: DP83848 is not recognized by the computer

Part Number: DP83848VYB

Hi team,

The 6-layer board drawn by the customer cannot be recognized by the computer. And the computer can be connected when the DP81848 circuit is made board separately. Does this mean a PCB layout issue? Could you help check the customer's PCB layout?

Here is the schematic

The PCB is a six-layer board. PCB layout:

Best Regards,

Amy Luo

  • Hi Amy,

    Could you clarify what is meant by the computer not being able to recognize the board? Is this during the schematic design/layout phase, or has the design already been fabricated and cannot linkup?

    Thanks,

    Evan

  • Hi Evan,

    The design has already been fabricated.

    Just like the screenshot above, when the network cable is plugged into the computer and the Ethernet connector end of the chip, the computer end will always show that the network cable is unplugged

    Best Regards,

    Amy

  • Hi Amy,

    Thank you for clarifying. The schematic and PCB layout look good, but it is difficult to verify without the file. Could you provide a block diagram of the application? In addition, are there any differences in the application between the 6-layer board layout and when the 848 circuit is made separately?

    Thanks,

    Evan

  • Hi Evan,

    The block diagram is as follows

    The ARM is the main chip, and the left side is connected with a high-speed USB PHY interface chip, an 83848 chip, and a 232 chip.The other side is connected to the FPGA for communication.

    There is no big difference. The 848 is a 4-layer board, and there are no other devices such as 232\ARM\FPGA chips.

    Below is the PCB layout for each layer

    top

    GND 

    signal

    power

    bottom

    Best,

    Amy

  • Hi Amy,

    when the DP81848 circuit is made board separately

    When the 848 is tested in this case, is the 848 a completely separate board from the master board, or is it acting as an interconnect?

    Is the customer able to read the PHY registers and provide a (0 to 1E) dump for each case?

    Thanks,

    Evan