BQ25619E: Charging Voltage Setting Issue

switch

Part Number: BQ25619E
Other Parts Discussed in Thread: BQ25619

Hi TI team,

The customer is experiencing an issue with the BQ25619E charging chip: when attempting to set the REG04 register to 4.450V (binary 11000), the device fails to charge properly. However, when using the default value of 4.200V (binary 01000), the charging function works perfectly.

Could you please help analyze the cause of this issue? The BQ25619E schematic diagram is provided below for reference. Thank you!

2 months ago

0 Michael Emanuel35 2 months ago

TI__Mastermind 42195 points

Hello,

Please elaborate. Provide battery voltage, VBUS voltage, SYS load, and a full register readout.

Regards,

Mike Emanuel

0 switch 2 months ago in reply to Michael Emanuel35

Genius 3920 points

Hello Michael，

1，Using BQ25619E default configuration with watchdog function disabled, the chip can charge normally with a charging current of 340mA (Test conditions: VBUS=5V, VBAT=3.9V, VSYS unable to load).

2，Using BQ25619E default configuration with watchdog function disabled, after setting the charging voltage to 4.48V and charging current to 800mA, the charging current displays 0mA. (Test conditions: VBUS=5V, VBAT=3.9V, VSYS unable to load). Below are the register configuration and read data during abnormal charging.

Write：

Read：

0 Michael Emanuel35 2 months ago in reply to switch

TI__Mastermind 42195 points

Hello,

Sorry to hear you are having trouble. Can you check the input, it looks like there is no VBUS detected...

Regards,

Mike Emanuel

0 switch 2 months ago in reply to Michael Emanuel35

Genius 3920 points

Hi Machael，

The input is confirmed to have 5V. Strangely, charging works with the default value, but once the charging voltage of the bq25619 is set to 4.48V, there is no charging current, and the read register shows no input exists.

0 Michael Emanuel35 2 months ago in reply to switch

TI__Mastermind 42195 points

What do the register logs look like then? What is the measured battery, system, and input voltage/current?

0 switch 2 months ago in reply to Michael Emanuel35

Genius 3920 points

Hi Michael，

The issue has been identified, Thanks!

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BQ25619E: Charging Voltage Setting Issue