HM5801 Datasheet | H&M Semiconductor

PMU for Portable Applications GENERAL DESCRIPTION The HM5801 is a integrated power management unit for small handheld portable applications. It contains a single-cell Lithium Ion battery charger, a synchronous step-down DC-DC converter and 2 Low Dropout Regulators. It allows charging from both wall adapter and USB port. When charging from wall adapter, the HM5801 increases the charging current automatically. The battery charger is a highly integrated charging management device targeted at space limited portable applications. It offers an integrated MOSFET and current sensor, reverse blocking protection, high accuracy current and voltage regulation, and charge termination. It charges a battery in three phases: trickle charging, constant current, and constant voltage. No external sense resistor is needed, and no blocking diode is required due to the internal MOSFET architecture. The thermal feedback regulates the charging current to limit the chip temperature during high power operation or high ambient temperature to maximize the charge rate without risk of overheating. The charge voltage is fixed at 4.2V, and the charge current can be programmed externally with a single resistor. The HM5801 automatically terminates the charge cycle when Features z Integrated switch for USB/AC Adapter supply z 120u A quiescent supply current(includes step-down DC-DC converters and two low dropout regulators) z Integrated single-cell lithium ion battery charger ‹ Auto thermal regulated ‹ Charging current up to 1.2 A ‹ Charging current adjusted by external resistor z Integrated step-down DC-DC converter ‹ Output voltage adjusted by external resistor ‹ Output current up to 800m A APPLICATIONS z MP3/4 z PDAs the charge current drops to 1/10 the programmed value after the final float voltage is reached. The HM5801 automatically re-starts the charge if the battery voltage falls below an internal threshold. The step-down converter is a high efficiency monolithic current mode...