Other Parts Discussed in Thread: TPS2378
Hello TI PoE experts,
Regarding to UPoE 4-pair powering, and the same time keeps standard 802.3at support. As you may already know, to support UPoE there can be two possible approaches:
- Powering up with 2-pair, then negotiate through CDP/LLDP to enable the other two pairs.
- Have two PDs on both ALT-A and ALT-B. This is a hardware approach called “forced mode”.
I know for the 2nd one you already have a reference SLVA625A by using two TPS2378. Please kindly let me know:
- Is that possible to use TI solution for the 1st approach? How about TI’s suggestion supporting UPoE?
- In case we use 1st approach with universal polarity bridges, the first two pairs shall have no problem powering up. However when the other two pairs join to powering, will it destroy the identification of the first two pairs and cause a shutdown?
This is a quite important question choosing solutions, looking forward to having your reply soon.
BR,
Jason (help customer to post the question)
