DP83867CS: latch and can't RESET_N duting ESD conatct test

user4782171

Intellectual 1560 points

Part Number: DP83867CS

Hi Team,

Here have an ESD application issue and questions that need your help for it.

ESD Condition: Air: +/-9KV: pass, contact : +/-7KV failed; SW: Linux Kernel 4.6.0

This Ethernet Phy can't recovery even do the HW RESET_N( Short to low more than 1sec to reset it).

Ethernet Phy can recvoery by Power off then to power on

Q1: As above can't RESET it through HW RESET_N pin. Any proposals to reset this Phy with Linux by FW?

Q2: Have any checking method to know the Phy is Crash.?

Best regards,

Albert Lee.

over 5 years ago

0 Rob Rodrigues over 5 years ago

TI__Mastermind 19780 points

Hi Albert,

Q1: If the HW reset pin is not working, reset using FW is not likely to work either. You should power cycle the DP83867 if it locks up like this.

Q2: To detect a device locking up like this depends on the system. You could try using MDIO to determine if the device is responding by reading basic registers 0x0 and 0x1 to determine if the PHY is active.

What ESD diode is being used on this board? Do you have schematics you can share?

Best Regards,

0 user4782171 over 5 years ago in reply to Rob Rodrigues

TI__Intellectual 1560 points

Hi Robert,

Thanks and I sent the circuit and layout drawings through the mail. Would you please help to have the suggestion for it?

Best regards,

Albert Lee.

0 Rob Rodrigues over 5 years ago in reply to user4782171

TI__Mastermind 19780 points

Hi Albert,

Due to the nature of the schematics, moving this discussion to email.

Finally, DP83867 ESD rating of +/- 8kV guarantees no damage to the device. This is referred to as class D performance.

Best Regards,

Interface

Interface forum

DP83867CS: latch and can't RESET_N duting ESD conatct test