LM5175EVM: LM5175并联二极管？

Hello Hideonbush,
Thanks for reaching out to us via e2e.

I am sorry, this is an international forum and I cannot understand Chinese.
Please enter your questions in English language.

Nevertheless, I will answer your question.

The diodes are placed in parallel to those FETs where the current could flow across the body diodes.
The idea is to keep high currents away from the body diodes and reduce the losses and the power dissipation of the FETs.
This only makes sense for higher power applications and only if the voltage drop of these external diodes is much lower than the voltage-drop of the body diodes of the FETs.

Best regards
Harry