Hello,
I have a strange issue with BQ25611D. The charger is only working using a PC or a lab power supply (without D+/D-) to charge. Otherwise (using a regular wall charger), the STAT LED is blinking very fast (way faster than 1Hz) and the charge current is not stable at all. Here is a video:
Video
The STAT LED is the white one. As you can see on the USB tester, the D+/D- values are pretty weird too, I don't know if it's related ?
I tried 3 different wall chargers with differents cables: same issue. I checked if the issue occurs on all charging states: it seems to only happen in fast charge mode. I tried to reset to default settings: same issue. I tried on two different boards: same issue. I tried to force the input current setting every second and I managed to get one of my wall charger to work 80% of the time, but no luck for the others and that's not the behavior I'm expecting, I was hopping to let the source detection do the job. I watched for status registers and measured the current while charging, here are the results:
Laptop USB (working properly):
- Charging state: 2 (fast charge)
- VBus good: 1
- VINDPM_STAT: 0
- IINDPM_STAT: 1
- BATSNS_STAT: 0
- Input current: 482mA
- Input voltage: 5.01V
- Current going to the battery: 487mA (there is a ~300mA load already plugged, but the issue is the same without load)
- Battery voltage: 3.09V (LiFePo4)
Wall charger (doesn't work) :
- Charging state: 0
- VBus good: 1 (??)
- VINDPM_STAT: 0
- IINDPM_STAT: 0
- BATSNS_STAT: 0
- Input current: moves a lot between 150mA and 450mA sometimes
- Input voltage: 5.11V
- Current going to the battery: -0.03mA (there is still the same load, and the battery is slightly discharging instead of charging)
- Battery voltage: 3.07V (LiFePo4)
Here are the settings that I use, but as I said, even with default settings I have the same issue.
const uint8_t CHARGING_INPUT_CURRENT{0b00000111}; // Charging current, see 9.5.1 in https://www.ti.com/lit/ds/symlink/bq25611d.pdf // 700mA default input current (updated with source detection)
const uint8_t CHARGING_VOLTAGE{0b00001010}; // Charging voltage setting, see 9.5.5 in https://www.ti.com/lit/ds/symlink/bq25611d.pdf // 3.590V with 15 minutes top off timer
const uint8_t CHARGING_FAST_CURRENT{0b00100001}; // Fast charge current, see 9.5.3 in https://www.ti.com/lit/ds/symlink/bq25611d.pdf // 1980mA fast charge, 500mA boost (OTG/charging?)
const uint8_t CHARGING_PRE_TERMINATION_CURRENT{0b01000010}; // Pre-charge and temrination current, see 9.5.4 in https://www.ti.com/lit/ds/symlink/bq25611d.pdf // 240mA pre-charge, 120mA termination
const uint8_t CHARGING_CONTROL_1{0b10001101}; // Charger control, see 9.5.6 in https://www.ti.com/lit/ds/symlink/bq25611d.pdf // JEITA Vset to Vreg, watchdog disabled, 90°C thermal regulation
const uint8_t CHARGING_CONTROL_2{0b11100000}; // Charger control, see 9.5.7 in https://www.ti.com/lit/ds/symlink/bq25611d.pdf // VINDPM to 3.9V (minimal input voltage?)
Here is my schematic:
(+3V0 is my LiFePo4 battery)
Do you have any idea of what should I do to fix this?
Best regards,
Gauthier
