DRV8350R: Internal Buck issue

Hi

Last picture is of signal after inductor.

and this signal is of before inductor :-

Regards

Imran Aftab

Hi Imran,

The internal buck is an LM5008A. Have you cross-referenced your schematic & layout with the LM5008A EVM and Webench Designer?

I don't see any inductor or feedback circuit on the schematic page you sent previously. However C46 of 1uF seems way too high for the feedback (FB) pin.

Thanks,

Matt

Hi Matt,

Thanks for quick response.

Please find the missing part in the below schematic. 

mdr-sch (1).pdf

Regards

Imran

Hi Imran,

I noticed you changed the value of C46 in the schematic. Is it recommended to keep this value based on other recommendations from LM5008A?

Thanks,

Matt

We are using as recommended 4.7 nF. What about rest of the design?

Hi Matt,

By increasing the value of inductor size problem has been almost resolved. Currently we dont have 1mH, we have ordered the same, as we will get it then we will try.

Thanks for Help

Regards,

Imran 

No problem, please let me know if you have further questions!

Thanks,

Matt