Dear all,
I'm trying to do the design step as described in the BQ34Z100 data sheet and i have some questions. I'm working on a custom board with a 9S Li-Ion configuration. I set the voltage divider with a 680K and 16.5K resistors. The pulses on BAT pin are about 900mV as they should be.
I set the design capacity and the design energy, number of cells and set VOLSEL to 1.
Now, i have to set the voltage divider with the maximum pack voltage and i enter 37800mV ( 4.2 x 9).
The next step is to calibrate the voltage. I have tried two different voltage and the results surprising me. I first tried with a full charged pack with a voltage of 37.7V. I entered 37700 and i pushed the calibrate button. The voltage measurement was near my value. Then, i checked the updated voltage divider value and it was 62345mV!!! The data sheet says that this value should be "slightly" different but not 2 time the initial value!
So, i tried the same step above with 37800mV as voltage divider and a pack with a nominal value of 34200mV. After the calibration, the measured value was about 800mV and the updated voltage divider value was 1674mV!!!
I think i do something wrong, can someone tell me what is the right way to do this step?
Thank you, best regards,
Pierrick.
