BQ25120A: BQ25120A SYS pin output question

Dustin Sun

Expert 1040 points

Part Number: BQ25120A
Other Parts Discussed in Thread: BQ25121A, TPS62800, TPS62740

Hi All expert :

Currently BQ25120A sys pin output default is 1.8V when charger wake up.

Is it possible to set up sys output pin is 3.3V when charger wake up ? any method from HW ?

0 Gautham over 5 years ago

Dustin,

Will a 2.5V VSYS work for MCU boot? Then you can look at the BQ25121A.

You will need I2C to change the VSYS voltage.

regards,
gautham

0 Dustin Sun over 5 years ago in reply to Gautham

Expert 1040 points

Hi Gautham :

MUC need 3.3V work.

if the charger shutdown, will LDO return to default value ? (1.8V)

is any method to set LDO ouput to 3.3V if charger from shutdown to wake up ?

0 Gautham over 5 years ago in reply to Dustin Sun

Dustin,

Best option would be to use a separate DCDC like the TPS62800 or TPS62740 from PMID.

You can use the LS/LDO but note that it will be in load switch mode by default.

regards,

gautham

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