Hello,
While configuring the internal registers with the I2C works only for the CRC enable, reference voltage enable and reference voltage selection. We are able to configure two different reference voltages (i.e., 3.0V and 1.5V) and are able to measure them at the VREF pin.
We are experiencing following issues while configuring the CELL_CTL and CONFIG_1 register of the BQ76925 chip.
1. Configure the CELL_CTL register by selecting the VCOUT_SEL to be '10' or '11' to have 0.5*VREF or 0.85*VREF at the VCOUT pin does not work as expected. Furthermore, configuring the BQ76925 to have internal temperature measurements at the VCOUT also does not work. In both of these settings, a ~10mV is measured with the multimeter.
2. Configure I_AMP_CAL to '1' in the CONFIG_1 register to measure voltage drop across 1mohms current sense resistor connected between SENSEN and SENSEP also does not work, provided that the current amplifier is enabled. According to the table 2 page 17 of the datasheet, the expected voltage at the VIOUT pin is 2V if the Isense = 0. In this configuration, we are also measuring ~10mV which is quite far away from the 2V expectation.
In our current hardware setup, we do not have cells connected at the VC0 .. VC6 pins. The VCTL and BAT pins are connected together and supplied with 24V.
I have tested the above mentioned configurations on three devices but no luck.
I would be happy to share further details if necessary and looking forward to your response.
best regards,
