PoE circuit diode spec of diode bridge circuit

K. Sasaki14

Could you let me know about diode spec of diode bridge circuit in PoE?

1A to 2A and 100V diode is recommended in your datsheet or EVM. Why is the 100V rating recommended? PD circuit max input voltage is 57V, thus over 57V voltage is not added normally. Then our customer would like to use 90V rating diode. Is there any concern about using this diode?

Best Regards,

Kohei Sasaki

over 10 years ago

0 Eric Wright over 10 years ago

TI__Mastermind 42795 points

Using a 90V diode will be fine.

0 K. Sasaki14 over 10 years ago in reply to Eric Wright

Guru 10200 points

Eric-san,

Thank you for your reply.

Is there any reason for recmmendation of 100V rating diode? Is it lerate to IEEE PoE specification? Or is it's reason only voltage margin?

Best Regards,

Kohei Sasaki

0 Darwin Fernandez over 10 years ago in reply to K. Sasaki14

TI__Mastermind 41760 points

Sasaki-san,
There is no IEEE spec that requires 100V. However, many customer's like to use 100V solutions because it adds robustness to the system. This is why you'll typically see them in our TI deisgns and EVMs. It helps account for voltage transients that the TVS might not be able to suppress. Like Eric said 90V should be okay too.

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PoE circuit diode spec of diode bridge circuit