The LTC4071’s shunt architecture enables unlimited voltage source compatibility. Only an external resistor is required to set the charge current for the device. Integrated battery pack protection includes low battery disconnect for undervoltage conditions and a zener for overvoltage conditions. The battery float voltage settings are pin-selectable 4.0V, 4.1V, and 4.2V, to allow for charging a wide variety of lithium-ion/polymer batteries. The maximum charge current is 50mA.