SGM41570

The SGM41570 is a synchronous Buck-Boost battery charge controller with NVDC power path management. It can provide high efficiency and low component count solution for 1-cell to 4-cell batteries charging applications.

The system is regulated slightly to be higher than the battery voltage, but not lower than the programmable system minimum voltage. Therefore, the system power is maintained even if the battery is completely depleted or removed. Dynamic power management (DPM) feature is also included that automatically reduces the charge current if the input current or voltage limit is reached. If the system load continues to increase after reduction of charge current down to zero, the battery enters the supplement mode and both adapter and battery power the system.

A wide range of input sources are supported for SGM41570, including traditional adapters, USB adapter and high voltage USB PD sources. The converter is configured as Buck, Boost or Buck-Boost during power-up, depending on the input source and battery conditions. The charger automatically switches among Buck, Boost and Buck-Boost without host control.

When the input source is absent, the SGM41570 can work in USB On-The-Go (OTG) mode to supply VBUS from battery. The OTG output voltage can be programmed from 3V to 20.56V with 8mV resolution. The slew rate of the output voltage transitions in OTG can be configured (by OTG current setting) to comply with the USB PD 3.0 PPS specifications.

If there is no external load on the USB OTG port and the system is powered by battery-only, the VMIN Active Protection (VAP) feature is supported. In VAP, the VBUS voltage is charged up by the battery and the energy is stored in the input decoupling capacitors. When the system requires peak power spike, the charge stored on the input capacitor discharges to maintain the system voltage at minimum system voltage.

Adapter current, battery current and system power are monitored in SGM41570. When the system power is too high and exceeds available power from adapter and battery together, a flexibly programmed nPROCHOT pulse is asserted to inform CPU for throttle back.