JAJSSD2A October 2023 – December 2023 BQ25638
PRODUCTION DATA
デバイスごとのパッケージ図は、PDF版データシートをご参照ください。
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, BATFET turns off. Otherwise, BATFET stays on to charge the battery. Converter startup requires the following conditions:
BQ25638 provides soft start when system rail is ramped up. Concurrently, the system short protection limits the output current to approximately 0.5A when the system rail is below VSYS_SHORT.
This device uses a highly efficient 1.5 MHz, fixed frequency pulse width modulated (PWM) step-down switching regulator. The internally compensated feedback loop keeps tight control of the switching frequency under all conditions of input voltage, battery voltage, charge current and temperature, simplifying output filter design.
In order to improve light-load efficiency, the device switches to PFM control at light load condition. The DIS_PFM_FWD and DIS_PFM_OTG bits can be used to disable the PFM operation in buck and boost respectively.