• State Resolved
  • Locked Locked
  • Replies 1 reply
  • Subscribers 63 subscribers
  • Views 151 views
  • Users 0 members are here
Support feedback
Options
Options
Related

This thread has been locked.

If you have a related question, please click the "Ask a related question" button in the top right corner. The newly created question will be automatically linked to this question.

BQ25798: BQ25798 input and battery provide Vsys simultaneously?

Mulin Chou
Prodigy 175 points
Part Number: BQ25798

Tool/software:

Hi,

Input：PD
system output：DC9V/3A
battery：3S1P

BQ25798 had this function?

VSYS can be powered from the battery through the battery FET, or from the input source through bust-boost. When the input source is not available, the battery FET is fully on, so the battery provides power to the system load.

the input source and battery provide power to the system simultaneously?

tks.

Mulin

  • +1
    TI__Guru**** 166916 points

    Hi Mulin,

    Yes.  If the system load is more than the input power can provide, the battery FET turns on full (VSYS=VBAT) and the battery discharge + converter output current goes to the battery.  Please note that SYS output is the higher of MINSYS or battery voltage, i.e. when input power is available VSYS starts at MINSYS and then follows the battery up to VREG as it charges.  The converter cannot provide a constant 9V at SYS.

    Regards,

    Jeff