TPS65261: Question about power sequence

Takahiro Saito

Expert 5325 points

Part Number: TPS65261

Hi team,

My customer wants to ask about power up/down sequence.
They want to use the following power up/down sequence.

Power up:Buck1→Buck2→Buck3
Power down: Buck1, Buck2 and Buck3 simultaneously

To acieve above sequence, they are cosidering to use the following way.

When power up, MODE and EN1,2,3 is set to High.
After powing up, MODE is set to Low.
And then, when powering down, EN1,2,3 is set to Low simultaneously.

Could you check if the above sequence work correctly?

Regards,
Saito

over 4 years ago

0 Jason Wang (BSR-MV) over 4 years ago

TI__Genius 9550 points

hi Saito,

you can't get your sequence which you mentioned. The power sequence will be locked after V7V voltage power up (PIN5 ).

0 Takahiro Saito over 4 years ago in reply to Jason Wang (BSR-MV)

TI__Expert 5325 points

Hi Jason-san,

Thanks. I appreciate your quick response.

I understand their method for sequencing doesn't work. They need alternate solution to achieve the sequence.

After powering up, if Vin is decreased lower than UVLO threshold, Buck1,2,3 should be turned off simultaneously.

Do you think this method is used for their required power down sequence?

Regards,

Saito

0 Zhao Ma over 4 years ago

TI__Genius 15135 points

Hi, Saito-san

The sequence can work correctly.

Power management

Power management forum

TPS65261: Question about power sequence