TPS54526: EN (enable) Pin issue

Rajneesh Jaiswal

Part Number: TPS54526

Hi All,

I am using TPS54526 buck converter to generate 5V from 15V input. The ENABLE pin is pulled up to Vin i.e, 15V through a 100K resistor as shown.

The issue is, on powering the board ON , theconverter is not enabled. On touching the EN pin with the multi meter probes, the converter starts working, and remains ON.

Please suggest a workaround.

Thanks

Rajneesh

over 5 years ago

0 Jason Wang (BSR-MV) over 5 years ago

TI__Genius 9550 points

hi,

R462 on the board or not? if yes, change R462 to 20K.

0 Rajneesh Jaiswal over 5 years ago in reply to Jason Wang (BSR-MV)

Prodigy 180 points

Hi,

R462 is not mounted. Only the pull up resistor of 100K is mounted. Tried changing the pull up resistor value to 10 K, but still same issue is there.

Thanks.

Rajneesh

0 Iven Su over 5 years ago in reply to Rajneesh Jaiswal

TI__Expert 8245 points

Hi,

The issue seems not resonable, please first double check the welding reliability, also you can change another sample to see if the issue exists. Thanks.

0 Jason Wang (BSR-MV) over 5 years ago in reply to Iven Su

TI__Genius 9550 points

Hi,

Please also check the solding quality. if some pins (or components) are void-solder?

0 Rajneesh Jaiswal over 5 years ago in reply to Jason Wang (BSR-MV)

Prodigy 180 points

The issue is resolved now. Added a resistor divider with 10K pull up/down .

Thanks

Rajneesh

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TPS54526: EN (enable) Pin issue