SLUSEC9B October 2020 – July 2024 BQ25618E , BQ25619E
PRODUCTION DATA
Refer to the PDF data sheet for device specific package drawings
After the input current limit is set, the converter is enabled and the HSFET and LSFET start switching. The system voltage is powered from the converter instead of the battery. If battery charging is disabled, the BATFET turns off. Otherwise, the BATFET stays on to charge the battery.
The device provides soft-start when system rail is ramping up. When the system rail is below VBAT_SHORT, the input current is limited to the lower of 200 mA or IINDPM register setting. The system load shall be appropriately planned not to exceed the 200-mA IINDPM limit. After the system rises above VBAT_SHORTZ, the device input current limit is the value set by the IINDPM register.
As a battery charger, the device deploys a highly efficient 1.5-MHz step-down switching regulator. The fixed frequency oscillator keeps tight control of the switching frequency under all conditions of input voltage, battery voltage, charge current and temperature simplifying output filter design.
The converter supports PFM operation by default for fast transient response during system voltage regulation and better light load efficiency. The PFM_DIS bit disables PFM operation if system voltage is not in regulation.