TPS2388: Port detection issue

chentsu chung

Part Number: TPS2388

Hi Team,

Test TPS2388 with normal ethernet cable(without PoE function), the POE LED turns on when RJ45 link up and link down.

Customer suspect that TPS2388 thought the ethernet cable as a PD, so the POE LED turns on, and then it turns off, and keeping on off.

And do Sifos test for detection and classification are all passed.

1. What could makes TPS2388 thought the ethernet cable as a PD device?

2. Is there anywhere I should look into?

over 5 years ago

0 Penny Xu over 5 years ago

TI__Genius 15685 points

Hi Chentsu,

How is the LED controlled? Through hardware or software? Can you send me the PSE schematic including the LED?

TPS2388 has to see 25K resistance to pass the detection and passing sifos proves that.

Thanks,

Penny

0 Thomas Lewis over 5 years ago in reply to Penny Xu

TI__Expert 5615 points

Chentsu,

We will be closing this thread and working the issue via this thread which deals with the same end customer issue. https://e2e.ti.com/support/power-management/f/196/p/865425/3201897#3201897

Please continue to follow the discussion there and work with TIer Jamie Tseng to answer any questions Penny asks. It will help us resolve this for you quickly.

Thank you for your local promotion of TI solutions,

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TPS2388: Port detection issue