• State TI Thinks Resolved
  • Locked Locked
  • Replies 4 replies
  • Answers 2 answers
  • Subscribers 63 subscribers
  • Views 346 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.

BQ34Z100-G1: current increase after LED configration

Bruce li
Genius 5580 points
Part Number: BQ34Z100-G1
Other Parts Discussed in Thread: BQ34Z100

Dear TI Experts,

My customer is evaluating BQ34z100 in a 3S project. They encountered below current issue,

1) After write dataflash at first, the fuction works well and power consumption is around ~135uA

2) Start configration LED indicatior with below parameter, then the power consumption increased to about ~700uA when LED is off, if LED is on, the current will be ~1.5mA.

Red represent 1, Green represent 0, external 4 LEDs, I2C communacation.

Attached is schematic and gg file. Could you kindly help to review the document and give some advices about the increaseing current after LED configration? Thanks a lot.

BQ34Z100G1-3S1P-8-2.gg.csv

BQ34Z100.pdf

  • 0
    TI__Mastermind 42535 points

    Hi Bruce,

    The LED driver can possibly increase the hw current draw when the circuit is enabled. Your config gg file looks OK. If the LED is on, we expect to see current draw be proportionally higher. Please recheck the current after resetting the LED comm configuration to 00 and seeing if it goes back to normal. The TRM, and the DS, give more information about the LED configuration and how REGIN and VEN combine to power external LED.

  • 0 in reply to Batt
    Genius 5580 points

    Dear Batt,

    Thanks a lot for your help, below update after check with customer:

    1) after set the LED comm configuration to 00 again, current is still ~700uA even when LED is off, however, if power off BQ34z100 and re-power on it , ther current will be back to ~135uA

    2) then set 00 to 33 again, current increase to 700uA again

    this phenomenon can be repeated everytime. Is it normal, could you kindly give some further advice?thanks a lot.

  • 0 in reply to Bruce li
    Genius 5580 points

    Dear Batt,

    I'm glad to tell you that the reason is found, the MOSFET at M7 positon, they take the wrong device on board and cause big current. You can close this post now, thanks a lot for your help.

  • 0 in reply to Bruce li
    TI__Mastermind 42535 points

    Hi Bruce,

    Thanks for the update.