JAJSQM7B June 2023 – February 2024 BQ25628E
PRODUCTION DATA
After the input current and voltage limits are set, the converter is enabled and the HSFET and LSFET start switching. If battery charging is disabled, the BATFET turns off. Otherwise, the BATFET stays on to charge the battery. Converter startup requires the following conditions:
The BQ25628E provides soft start when the system rail is ramped up by setting IINDPM to its lowest programmable value and stepping up through each available setting until reaching the value set by IINDPM register. Concurrently, the system short protection limits the output current to approximately 0.5 A when the system rail is below VSYS_SHORT.
The device uses a highly efficient 1.5-MHz, fixed frequency pulse width modulated (PWM) step-down switching regulator. The internally compensated feedback loop keep tight control of the switching frequency under all conditions of input voltage, battery voltage, charge current and temperature, simplifying output filter design.
The device switches to pulse frequency modulation (PFM) control at light load condition. The PFM_FWD_DIS bit can be used to disable the PFM operation.