TPS23754EVM-383：I have some questions about tps23754 and would like to consult

Hello Runtao,
Hope you do not mind, but E2E uses English to communicate.

In the picture you have circled L3,
its purpose is to act as the output inductor of the active clamp forward DC/DC converter. It is needed as a component of the forward converter to store energy.
If you want to use a flyback converter, which does not have this output inductor, I would advise looking at the TPS23754EVM-420 EVM instead.

If you are asking about L1, it is acting as a low-pass pi filter.

Let us know if you have further questions,
Sarah

vx700ar_230600.pdfI used a flyback topology,Could you please help check the schematic diagram?

Hi Runtao,
May I know what transformer you are using at U49?
I am not familiar with this EP_T838S, and cannot find any information on it, but it appears to be a forward converter.
Could you send the datasheet for this component, if able?

It seems as though most of your connections on the secondary side are still for a forward topology,
you will need to adjust these for flyback topology.

PMP6812 is a reference design for the TPS23754 using flyback topology for a 12V output:
https://www.ti.com.cn/tool/cn/PMP6812
This schematic could be a better reference suited to your needs.

Thank you,
Sarah

EP-T838S翼腾完整承认书(4).pdf

HI Sarah,

      I found that the conversion efficiency of PMP6812 is about 4% lower than TPS23754EVM-383.

Hi Runtao, 

Yes, that is true. If you want the higher efficiency of the TPS23754EVM-383 design, then you will have a forward topology, since it has a forward converter design.

And so you will need to implement the L3 capacitor which you first asked about, and follow the rest of the connections depicted in the EVM schematic.

Best,
Sarah

Hi Sarah,

   Thanks for your replay.For higher conversion efficiency, active forward clamping will be used.Could you please help check the circuit?

    Another thing, can I make some adjustments when referring to the design of TPS23754EVM-383? The VCC input uses flyback mode, and other places refer to TPS23754EVM-383.

7510.vx700ar_230600.pdf

Hi Sarah,

     The response regarding 'Another thing, can I make some adjustments when referring to the design of TPS23754EVM-383? The VCC input uses flyback mode, and other places refer to TPS23754EVM-383.' specifically refers to he following drawing.

4604.vx700ar_230600.pdf

Hi Runtao, 
Yes, I think your adjustment would work, if you switch the order of VD3 and R197, so they follow the diagram below:

Else, all your connections look good to me!

Best,
Sarah