DP83825IRMQR OSC not working CMOS

Hi Baskar,

Can you help me further understand the issue - are you able to see a 25M input on XI?

I recommend removing the PU on MDC and adding a 2.2kohm PU to MDIO.

Thank you,

Evan

Hi,

Thanks for your information, 

There is no 25Mhz input on XI and the CMOS crystal is not started with this phy chip .

Is it the MDIO PU  is related to impact the chip CMOS oscillator start-up, please confirm it?

We are struggling almost 30 days due to the phy chip oscillator issue with CMOS, Please confirm the right issue of the mismatch components in the circuit, 

Hi Baskar,

MDIO PU is unrelated to oscillator start-up, but it may affect register access.

Is the PHY alive? Please probe across RBIAS and confirm the voltage seen.

Thank you,

Evan

No, There is no voltage across the RBias resister.
Is it due the pulse transformer loading to chip or due to oscillator start-up issue   

Hi Baskar,

The root cause appears to be the power circuit.

No voltage across RBIAS is a symptom of the PHY not being powered. The oscillator will not show an input unless the PHY is powered.

Thank you,

Evan