• State Resolved
  • Locked Locked
  • Replies 4 replies
  • Subscribers 63 subscribers
  • Views 379 views
  • Users 0 members are here
Support feedback
Options
Options
Similar topics

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.

BQ24031 - Relation with BAT voltage

Hirotaka Matsumoto
Guru 27545 points
Other Parts Discussed in Thread: BQ24031

Hello,

Would you mind if we ask relation with BAT voltage on BQ24031.

<Question>
Please tell us difference of initial behavior, when BAT voltage is above 3.0V or under 3.0V.
And then, is DPPM voltage relation with  BAT voltage(in case of under 3.0V or above 3.0V)?

Kind regards,

Hirotaka Matsumoto

  • 0
    TI__Genius 13700 points

    Hello Hirotaka,

    When VBAT is below 3.0V the device will operate in precharge mode which is a constant current charging with a current that is below the designated fast charge current. This magnitude of this precharge current is set by Eq. 4 on Pg. 22 of the datasheet.

    Once VBAT is above 3.0V the device will enter fast charge mode which will raise the charging current to the fast charge current limit which is set using the ISET pins.

    The DPPM voltage is relative to the voltage seen at the OUT pin, however the voltage of this pin is compared to the voltage on the BAT pin and the DPPM threshold (See note 2 on Pg 2 of the datasheet). When the voltage on this pin droops due to a voltage droop on the input pin  the device will lower the battery charging current to allow the voltage on the OUT pin to rise.

  • 0 in reply to Ryan May
    Guru 27545 points

    Hello Ryan San,

    Thank you for your updata.
    We'd like to confirm one point.

    If the VBAT is above 3.5V or below 3.5V～3.0V, is this content included in above 3.0V condition?
    Will the result be the same?

    Kind regards,

    Hirotaka Matsumoto

  • 0 in reply to Hirotaka Matsumoto
    TI__Genius 13700 points

    Hello Hirotaka San,

    I am not entirely sure I understand your question.

    If the VBAT pin is above 3.5V the device will operate in fast charging CC/CV. The threshold for this behavior is above 3.0V typical so as long as the VBAT pin is biased with at least 3.0V the bq24031 will attempt fast charging.


    The device will support supplement mode as long as the VBAT is above 2V.

    Let me know if I misunderstood your question.

  • 0 in reply to Ryan May
    Guru 27545 points

    Ryan San,

    Thank you for your excellent comment!
    Your reply correspond to our questions.

    Kind regards,

    Hirotaka Matsumoto