DP83848I: ISSUE: PHY freezes on power up

Hi,

The previous thread is locked.

I did what you recommended and the PHY still doesn't work. 

This looks like a bug in the design of the chip. the chip is communicating so there is no reason why the PHY itself will latch-up, and if there is a latch-up then why a software reset fixes the issue. the hardware reset is with a descent delay from power up so those two resets should behave the same. 

Thanks,

Dor.

I copied the data from the previous thread:

Every couple hundred of power ups the PHY freezes. the PHY receives the 25MHz clock but not returning anyting on the rx_clk or tx_clk.

when we do a rst to the PHY (without reseting any other componnent) the PHY unfreezes. the MDIO is working so hardware or software reset both succeed in unfreezing the PHY.

the 3.3V was monitored through startup there is no overshoot and the startup time is ~1ms.

RXD[0] was also monitored during reset from powerup and the line was stable.

Is the issue familiar?

Is conducting software reset after every powerup enough to ensure this issue will not occur on startup or in steady state operation?

same test was made on DP83848VYB and the issue did not appear with this product. since the product is with different footprint I cannot switch to use with it instead.

 Register state of the PHY in normal operation and in failed state:

Thanks,

Dor