The AAT3604B is a micropower PMU optimized for maximum lithium-ion (polymer) battery life both in operational and standby mode. The total no load current into V IN when all functions are enabled is only 70μA. The AAT3604B is a highly integrated device which simplifies system level design for the user with minimal external components required. It contains a step-up (boost) converter, a step-down (buck) converter, an LDO regulator and a single-cell Lithium Ion/Polymer battery charger in a single PMU. The device also includes a load switch for dynamic power path/sleep mode operation for processor core voltage, making it ideal for ultra low power portable devices. The battery charger is a complete, thermally protected constant current/constant voltage linear charger. It includes an integrated pass device, reverse blocking protection, high accuracy current and voltage regulation, charge status indication, and charge termination. The step-up DC/DC converter is a high efficiency boost converter capable of 27V maximum output voltage. It is the ideal power solution to power OLED, LCD, and CCD applications. The step-up converter offers a true load disconnect feature which isolates the load from the power source when EN1 is pulled low. This eliminates leakage current and isolates the output while the device is disabled. The step-down DC/DC converter is integrated with internal compensation and operates up to a switching frequency of 1.6MHz, thus minimizing the size of external components while keeping switching losses low and efficiency high. The LDO regulator offers 60dB power supply rejection ratio (PSRR) and low noise operation, making it suitable for powering noise-sensitive loads. The AAT3604B is available in a space-saving, thermally enhanced 24-pin QFN44 package. *Available exclusively outside of the United States and its territories.