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DP83620: MII bus idle

Part Number: DP83620


We've designed a new board with the DP83620 connected to the Micrel KSZ8873MML port 1. 

When the reset and the powerdown signal are de-asserted, I can see a pulse on the MDI interface that look like the auto-negotiation pulse. No link is created when I connect it to another Ethernet device. (laptop)

I've tried to force the link to 100Mbps Full duplex and the only behavior that I got is tx pair now showing active link. Nothing on the RX. 


During all this, the MII bus is idle and even TX_CLK and RX_CLK are low. We don't have any communication on the MDIO bus.

I've included the schematic page.

PHY Schematic Page

Is there any initialization that need to be done thru MDIO? Is there a missing strapping resistor?