A highly integrated one cell battery management chip for wearables

Herein is presented a battery management chip without external charging and discharging MOSFETs that promotes the miniaturization of wearable devices and reducing the size of battery management system on printed circuit boards (PCBs). The battery management chip is designed to integrate the discrete charging and discharging MOSFETs into the chip, even removing current sense resistor significantly. Using the proposed adaptive substrate selecting (ASS) technology, the same protection function of the traditional battery management chip is realized, which greatly saves the area cost of the chip. Based on the 0.18 μm 5 V process, the circuit and the switch have been integrated into a single lithium battery management chip. The measurements show that the chip can reliably protect the battery from overvoltage, under voltage and overcurrent with low power consumption.