TPS23730EVM-093: TPS23730EVM-093 reference_48VOUT design from 48VIN~56VIN workable ?

Hi Diang,

Thanks for your sharing, they are very useful information about the reference design and the suggested transformer for me.
Howerver, there are some question abou 54V reference schematic that I am not very clear understand.

1. Does the circuit that used on secondary side of transformer be the application of RCD snubber(D16, D17, C15,R30, R31) which like the RCD snubber(R33,C23,D18) at primary side of transformer?

2. There are many non-installed components at secondary side of transformer, is there any situation that I should make them installed?

And could you help review the schematic of TPS23730 as attachment?
Please let me know if you have any suggestion.
I have sent my TPS23730 schematic by email.

Hi Ching-Fei,

I had sent you the review comments in email.
1. Does the circuit that used on secondary side of transformer be the application of RCD snubber(D16, D17, C15,R30, R31) which like the RCD snubber(R33,C23,D18) at primary side of transformer?

Yes, it looks like the passive clamping circuit with RCD (R33,C23,D18) on primary side. But it is placed on the secondary side. I think it is for the same purpose. 

2. There are many non-installed components at secondary side of transformer, is there any situation that I should make them installed?

These non-installed components are for optional sync FET, line filter, snubber circuits... Depending on your design preference and requirement, you can choose use them or not.  

Best regards,

Diang

Hi Diang,

Thanks for your feedback, I have updated my schematic base on your suggestion. However, there are some items that I don't clear understand that I list in the mail. And please let me know if the schematic that I send have any other concern.

On the other hand, POE use lots of synchronous control on secondary side of transformer, but we don't very familiar with it. Does TI have some information for us to study?

Hi Ching-Fei,

Thanks for your updates.

I received your email and I should be able to reply in 3 business days.

Best regards,

Diang

Hi Diang,

Sure, review schematic need to take times. I will wait your feedback, thanks so much.

Hi Ching-Fei,

You are welcome! I had replied you in email for your schematic.

The paper below may be helpful. Usually for 48V and 51W output, the efficiency of sync FET flyback and diode flyback may not have significant difference.  

Under the Hood of Flyback SMPS Designs Article (https://www.ti.com/seclit/ml/slup261/slup261.pdf)

Best regards,

Diang

Hi Diang,

I will provide you final schematic to review after the P/N transformer finished applied. However, the paper you provide that I cannot download, it seems that have the usage rights. Could you just send me the pdf file of this paper to me?
Thanks so much.

Hi Ching-Fei,

Please try the link below:

https://www.ti.com/lit/ml/slup254/slup254.pdf

Best regards,

Diang

Hi Diang,

Thanks, I could download the pdf file of this paper now.
And I have sent you the final schematic to you for reviewing by email, please let me know if you have any design concern.

Hi Diang,

Thanks so much about your reviewing, the SCDIS that you mention by mail I will discuss with my EE.

Hi Ching-Fei,

No problem!

As we already connected in email, I would prefer to closing this thread for now. If you have a different question please open a new thread. 

Best regards,

Diang