LM3643: LM3643 used without output cap on PASS mode

popescu Lucian

Part Number: LM3643

Hi,

Due to some space limitation I`m forced to use the LM3643 without the output cap on PASS mode.

Looks to be only a bit of undershoot.

Did someone use the same configuration ?

Thanks

Luci

0 Ives Li 11 months ago

Hi Luci,

If you use the LM3643 in PASS mode, the inductor could be removed to save the space, but the output cap is still recommended to be connect.

Thanks!

0 popescu Lucian 11 months ago in reply to Ives Li

Hi Li,

I know is recommended to have the output cap but based on measurement we have the overshoot of the LED PWM a bit larger.

Thanks !

0 Ives Li 11 months ago in reply to popescu Lucian

Hi Lucian,

Could you please provide your schematics, layout and the measurement waveform, so I can provide better suggestion for you.

Thanks!

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