MCP73871 USB/AC Battery Charger Microchip Technology MCP73871 USB/AC Battery Charger is a 1A fully integrated linear solution for system load sharing and Li-Ion and Li-Polymer battery charge management with AC-DC wall adapter and USB port power sources selection. The MCP73871 is capable of autonomous power source selection between input or battery. This device employs a constant current/constant voltage (CC/CV) charge algorithm with a selectable charge termination point. The constant voltage regulation is fixed with four available options including 4.10V, 4.20V, 4.35V, or 4.40V to accommodate new and emerging battery charging requirements.