TPS548A28: Ripple waveform

Hailiang Zhang

Part Number: TPS548A28

Tool/software:

Hi Team,

Pls check the ripple of TPS548A28 below. I would like to know why the ripple voltage drops twice during the freewheeling phase. Please refer to the waveform shown in the red circle below. Could you pls help comment?

Regards,
Hailiang

over 1 year ago

0 Ryan Chen over 1 year ago

TI__Genius 15187 points

Hi Hailiang,

Can you please attach ripple waveform and schematic?
Best,
Ryan

0 Hailiang Zhang over 1 year ago in reply to Ryan Chen

TI__Genius 11120 points

Hi Ryan,

Pls check the attached waveform, and see the schematic via Email.

Regards,
Hailiang

0 Ryan Chen over 1 year ago in reply to Hailiang Zhang

TI__Genius 15187 points

Hi Hailiang,

The schematic looks okay, the only thing missing is the CFF which is required for the design. Recommend a value of 680 pF. Is the persistence on for this measurement? How is the ripple being measured? Is it measured with SMB connector or across the output cap with tip and barrel?

Best,

Ryan

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TPS548A28: Ripple waveform