TPS54331: very important noise at the output of the buck

Hugo LE COZANNET

Prodigy 10 points

Part Number: TPS54331

Hello,

I use a TPS54331D but I have noise like in the following photo,

scope

here is my montage.

Does anyone have any idea of my problem?
I want an input voltage of 7V and 18V with an output voltage of 3.3V and 3A.

the noise rises to 6V and repeats about every 2 ms. The rest of the time, I have 3.3V output

over 4 years ago

0 Zhao Ma over 4 years ago

TI__Genius 15135 points

Hi, Hugo

I review the schematic, it looks okay.

1. Confirm the test condition of the issued waveform.

Vin=? loading=?

2. If you increase the loading slowly, and check if still have this problem.

3. Could you send me the layout file? including top and bottom layer.

0 Hugo LE COZANNET over 4 years ago in reply to Zhao Ma

Prodigy 10 points

Hello,

I am sincerely sorry, we have solved our problems. We were not drawing enough current for the buck to be effective and we also had a ground problem (forgotten ground plane which created a lot of noise)

All my excuses,

Hugo LE COZANNET

0 Lishuang Zhao over 4 years ago in reply to Hugo LE COZANNET

TI__Expert 7500 points

Hi,

Thanks for your feedback. Glad to see that the issue is solved. We will close this thread.

Thanks,

Lishuang

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TPS54331: very important noise at the output of the buck