Extracted from data sheet:The MCP73871 device employs a constant current/constant voltage (CC/CV) charge algorithm with selectable charge termination point. To accommodate new and emerging battery charging requirements, the constant voltage regulation is fixed with four available options: 4.10V, 4.20V, 4.35V or 4.40V. The MCP73871 device also limits the charge current based on the die temperature during high power or high ambient conditions. This thermal regulation optimizes the charge cycle time while maintaining device reliability.