An event-driven ultra-low-current battery management system with reconfigurable linear regulator for multi-cell battery applications

This paper presents a battery management system for multi-cell Lithium-Ion battery applications. The sub-microampere sleep current and an event-driven wakeup mechanism of the proposed system are developed to improve the battery lifetime. Also presented is a reconfigurable linear regulator, in which an adaptive frequency compensation scheme ensures the stability and maintains low no-load quiescent current of the regulator with and without an external power transistor. Implemented in a 40-V, 0.25-μm BiCMOS process, the battery management system consumes 0.8 μA in the sleep mode, achieving considerable improvement over the state-of-the-art counterparts. The proposed linear regulator can take an input from 4.2 V to 36 V and deliver a maximum 50-mA load under the external power transistor mode with only 3.9-μA no-load quiescent current.