BQ25121: LSCTRL pin

Dima S

Prodigy 220 points

Part Number: BQ25121
Other Parts Discussed in Thread: BQ25120A, BQSTUDIO

Pulling the LSCTRL Pin LOW does not turn off the LS/LDO out.

But when i also write to the PMIC register (MSB of register 0x07u, changed to 0x7C) it does shutdown the LS/LDO.

Couldn't find anything about it in the data sheet.

over 5 years ago

0 Raheem over 5 years ago

TI__Mastermind 21590 points

Hello Dima,

This is expected behavior as explained in Table 9 of the datasheet shown below

0 Gautham over 5 years ago

TI__Genius 12475 points

Dima,

Please refer to Table 9 on the BQ25120A datasheet for LSCTRL settings.

Are you actively pulling it low or leaving it floating (LSCTRL has an internal pulldown)

regards,

gautham

0 Dima S over 5 years ago in reply to Raheem

Prodigy 220 points

Can you please explain the Formula specified in the table below?

What is the LS_LDOCODE?

What should i write to configure a 3.1 V? 3.3V?

and waht is the difference between LSW and VLDO? ( in your table)

Thanks!

0 Gautham over 5 years ago in reply to Dima S

TI__Genius 12475 points

LS_LDO code is the value on the register itself. i would recommend you use BQStudio to help you with configuration on BQ25120A. It has a dropdown which will calculate the hex code for you automatically.

LSW is Load Switch (not regulated) and LDO is regulated output. For 3.1V LDO, you will write 0xDC to register 0x07.

Regards,

Gautham

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BQ25121: LSCTRL pin