The LP7811 is an advanced TWS charging case management IC targeting to improve the total battery run time of the TWS earphones. The IC features a switching charger protects up to 30V input voltage and digitally programmable up to 1.7-A charge current via an I2C bus.
The smart discharge voltage management feature tries to maximize the battery run time with ultra-low dropout charging scheme. The VOL and the VOR outputs track the battery voltages of the earphones when operating together with the companion linear charger (LP408X) in the earphone, minimizing the power loss. An NTC interface isoffered to manage the charge and discharge operation based on the battery temperature sensed by the NTC resistor. Additional silicon temperature management ensure the safe operation. Earphone insertion and removal detections simplify the design of the earphone detection.
The IC supports two independent bidirectional communication bus to the left and right earphone. An I2C bus is offered for programmability and flexibility of the device.The quiescent current is 5-uA in standby mode. The whole system is in a small 24-pin 4x4 QFN package.