TPS23754: PoE PD design support Pos/Neg output rail

Hi Eddie,

Does the customer want a single design with 4 outputs or do they want a single +/- 12V design and two seperate 5V & 1.5V designs?
Does the PD only requirement apply to all output combinations? I can see PMP7355 being a good fit, but it has an integrated PWM controller.

 I can better assist you after gaining clarity around these requirements.

Some initial comments:
- To my knowledge, we do not have a ready made +/- 12V PoE reference design, but I can recommend something close that can be modified.
- 5.5V & 5V designs would be able to meet the class 2 (6.5W at PD) requirement.
- +/- 12V design would need to be at least class 3 (13W at the PD).

Regards,
Tom A.

Hi Tom,
Thanks for comments, please recommend the closest reference and we can suggest customer to modify,
Regards
Eddie

Hi Eddie,

Here is my recommendation for 5.5V / 1.5A & 5V / 1.5A:
- PMP7355 for lower cost (5V/2A)
- PMP9175 for higher efficiency (5V/2.3A)
- each design can be modified to accomodate 5.5V out.
- Both designs use TPS23753A which is an integrated PD+PWM controller. Let me know if you want older PoE designs with PD separate from PWM controller.

I am checking with my colleague about the +/-12V design.

Regards,
Tom Amlee
Applications Engineer, PoE

Hi Eddie,

Can you confirm if these are 4 separate converter designs requirements? Or is it the voltage rails of a single board? The reason I ask is because it can be either a 13W design or a >35W design which will mean completely different PD controllers that we would recommend. Please confirm, or a block diagram of the customer's system showing the power/voltage rails will help. Thanks!

Eddie,

It has been over a week since we last heard from you. Does this matter still require our support?

Thank you for your local support,

Hi Thomas,

Do we have other suggestion? customer concern our suggest solution PCB size is larger than competitor.

Thanks

Eddie

Eddie, What is their target PCB size?

Also, if you would answer the questions from Darwin's thread, that could help us as well (copied and pasted here).

• Can you confirm if these are 4 separate converter designs requirements? Or is it the voltage rails of a single board? The reason I ask is because it can be either a 13W design or a >35W design which will mean completely different PD controllers that we would recommend. Please confirm, or a block diagram of the customer's system showing the power/voltage rails will help.

Also, as you mentioned there is a competitive solution, we could take this thread offline and dig into that more deeply.  Feel free to email me through the TI system if wanting more help and mention this thread.

Thanks for your local support,