Hi,
Good Day.
The customer is in the process of programming a product that uses 2pcs of BQ25708 charger ICs. But he is having an issue when the output voltage is above a certain level and he sends a command to change the charge current, in this situation, the charger IC detects an SYSOVP error and terminates charging, therefore his questions are these:
1) What voltage is measured to used to determine an SYSOVP as compared to the voltage set at the CELL_BATPRESz?
In fact to eliminate such an issue he had the circuit with CELL_BATPRESZ fixed at 75.9% of REGN (using a resistor divider consisting of a 330kohm in series with 1.04Mohm). He had also read on a post on E2E that fixing the CELL_BATPRESZ pin to the ground also sets the SYSOVP voltage to 19.5V and he is trying that right now.
However, the issue remains the same, whereby:
1) If he is to charge a 2s battery the charger works perfectly.
2) If he is to charge a depleted 4s battery the charger also works perfectly.
3) If he is to charge a partly discharged 4s battery SYSOVP is triggered either immediately, or after he try to change the charge current.
Please advise. Thank you very much.
Best Regards,
Ray Vincent
