Maxim Integrated Products’ MAX8819A is a highly integrated power-management IC (PMIC). It integrates a single-cell, lithium-ion (Li+)/lithium-polymer (Li-Poly) charger with proprietary Smart Power Selector circuitry that seamlessly distributes power within the system. To reduce BOM cost, the MAX8819A integrates three 2MHz step-down converters and one step-up converter with serial-step dimming control for powering two to six WLEDs. Offering a solution footprint of less than 90mm2 with a low 1mm height, the MAX8819A is the smallest complete power-management solution for battery-operated devices. This device is ideal for use in portable media players, MP3 players, GPS devices, and other handheld applications.
The MAX8819A's Smart Power Selector circuitry manages power distribution between a battery, USB/AC-to-DC adapter, and system load. When a USB or AC-to-DC adapter is connected, the input power that is not used by the system load is used to charge the battery. In addition, Smart Power Selector circuitry allows the system to operate with no battery or a deeply discharged battery. The Smart Power Selector also provides thermal-limiting circuitry that reduces the battery-charge rate to prevent the charger from overheating. All necessary power switches and current-sense circuitry are included on the chip-no external MOSFETs are required.
Maxim Integrated Products, www.maxim-ic.com