BQ25121: LSCTRL PIN and PMIC init.

Dima S

Prodigy 220 points

Part Number: BQ25121

Hi ,

When working with no battery connected to device, only external 5V power.

On Boot, when PMIC is in default state.

If LSCTRL pin connected to PMIC is LOW then i can't configure the PMIC registers, get some I2C error.

if LSCTRL is pin is high all is good.

This happens when there is no battery attached at all to device.

over 5 years ago

0 Gautham over 5 years ago

TI__Genius 12485 points

Dima,

Is the MCU powered from VSYS? Are the I2C lines pulled up to VSYS?

regards,
gautham

0 domenyko over 5 years ago in reply to Gautham

TI__Genius 9655 points

Hi Gautham,

I’m the FAE who support the project. The MCU is powered from VSYS and the I2C resistors are pulled up to VSYS.

Regards,

Domenico

0 domenyko over 5 years ago in reply to domenyko

TI__Genius 9655 points

Hi Gautham,

is it correct to say that since the battery is not present there is a fault in the boot operation process and so the VSYS is disabled ?

So is a maual operation on LSCTRL required to enable the LDO ?

regards,

Domenico

0 Gautham over 5 years ago in reply to domenyko

TI__Genius 12485 points

Domenico,

LSCTRL Manuel mode is okay. But that shouldn’t have anything to do with the I2C configurability of the part itself. Can you post your schematic? Do you have plots of I2C along with PMID and VSYS?

Regards,
Gautham

0 Gautham over 5 years ago in reply to Gautham

TI__Genius 12485 points

Domenico,

I just got back from time off. I saw your email and will reply there shortly.

thanks,
gautham

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BQ25121: LSCTRL PIN and PMIC init.