TPS23751: About PoE authentication

TATSU Numa

Part Number: TPS23751

Hi Team

Is there a time limit for detection and class identification?

There are voltage specifications in the data sheet, and as shown in the figure below, Detection is 2.7~10.1V and Classification is 14.5~20.5V.
Are there any time regulations for detection and class identification at this voltage?

best regards

TATSU

over 2 years ago

+1 Diang Xing over 2 years ago

TI__Mastermind 37111 points

Hi TATSU,

Thanks for reaching out.

For 802.3 AT standard, classification time is 6-30ms per event (T_CLE). Max detection time (T_DET) is 0.5s.

Best regards,

Diang

0 TATSU Numa over 2 years ago in reply to Diang Xing

TI__Intellectual 800 points

Hi Diang

if possible could you also help me following question from customer?

We believe that your response is an authentication event on the PSE side.
What I would like to ask this time is whether there are time regulations on the PD side as well?

best regareds

TATSU

0 Diang Xing over 2 years ago in reply to TATSU Numa

TI__Mastermind 37111 points

Hi TATSU,

PSE is the signal sending side. PD is the signal receiving side which is relative passive during the detection and classification. I think PSE drives these hand shake signal timings.

From PD normally they are some comparators to sense the PD input voltage and decide turn on/off some voltage regulators / switches.

Best regards ,

Diang

Power management

Power management forum

TPS23751: About PoE authentication