Other Parts Discussed in Thread: EV2400, BQSTUDIO
Hi,
We are using BQ25713 as part of main charge control IC in our battery back up based design.
Battery used is 2-terminal 3SP1 with 10.7V as max voltage.
We are using following register setting
ChargeCurrent() [Reg 0x03/02] - 1A
ChargeVoltage() [Reg 0x04/05] - 10.7V
InputVoltage() [Reg 0X0B/0A] - 2V
IIN_HOST() [Reg 0x0F/0E] - 3.3A
MinSystemVoltage() [Reg0x0D/0C] - 10.7V
When we do I2C programming of BQ25713 using Main power supply(12V) , I2C communication will happen and we are able to read the register, however when we disconnect Main power supply and connect only battery, I2C programming of BQ25713 is failing(all the I2C voltage levels are as expected), and we will not able to read any register.
We are observing this issue in not all the boards but almost on 20% of the boards.
OTG/VAP signal is set high ie 3.3V
When only Main is connected,
ILIM_HIZ - 1.21V
CELL_BATPRESZ - 3.6V
REGN - 6V
CHRG_OK - 3.3V
When only battery is connected,
ILIM_HIZ - 0V
CELL_BATPRESZ - 0V
REGN - 0V
CHRG_OK - 0V
Board -2 | OTG EN =1 | OTG EN =0 | ||
Only Main | Only Battery | Only Main | Only Battery | |
OTG/VAP | 3.3V | 3.3V | 0V | 0V |
CHRG_OK | 3.3V | 0V | 3.3V | 0V |
ILIM_HIZ | 1.21V | 0V | 1.21V | 0V |
CELL_BATPRESZ | 3.6V | 0V | 3.6V | 0V |
REGN | 6.4V | 0V | 6.4V | 0V |
VBUS | 12V | 1.5V | 12V | 1.5V |
VSYS | 10.7V | 9.5V(Battery v- 10.2V) | 10.7V | 9.5V(Battery v- 10.2V) |
Could you please help us to solve this issue or give us a direction .
Best Regards,
Sudha Nayak