PMP41009: About a filter capacitor on the VS input

yuudai.nishikawa

Part Number: PMP41009

Why place a filter capacitor on the VS input even though specification states "Avoid placing a filter capacitor on this input which interferes with accurate sensing of this waveform"?
Also, what noise effects are being considered?

over 1 year ago

0 Linda Ye over 1 year ago

TI__Intellectual 1110 points

Hi Yuudai, The noise triggered the input under voltage protection, that is why I placed a capacitor on the VS pin.

0 yuudai.nishikawa over 1 year ago in reply to Linda Ye

Prodigy 20 points

Thank you for your reply.

Can the VS pin work well with a capacitor?

(For example, to accurately sense the timing information to achieve valley-switching and the duty-cycle of the transformer secondary current.)

+1 Linda Ye over 1 year ago in reply to yuudai.nishikawa

TI__Intellectual 1110 points

Yes, it works well.

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PMP41009: About a filter capacitor on the VS input