BQ41Z50 Battery Fuel Gauge and Protector

The BQ41Z50 from Texas Instruments is a fully integrated, single-chip, pack-based solution that provides a rich array of features for gas gauging, protection, and authentication for 2-series, 3-series, and 4-series cell Li-ion, LiPO, and LiFePO₄ battery packs.

Using its integrated high-performance analog peripherals and ultra-low-power 32-bit RISC processor, the BQ41Z50 device measures and maintains an accurate record of available cell capacity, voltage, current, temperature, and other critical battery parameters and reports them to the system host controller over an SMBus v3.2 compatible interface. The BQ41Z50 device utilizes Dynamic Z-Track™ technology to report highly accurate charge states even under dynamic loading conditions. This technology also improves the accuracy of TURBO mode by providing the available maximum power and maximum current to the host system.

The BQ41Z50 device provides an array of battery safety functions, including overvoltage, overtemperature, overcurrent in charge and discharge, and short-circuit in discharge protections. System safety functions incorporate FET protection for the N-channel FETs and cell disconnection detection. The device firmware provides software-based first- and second-level safety protections against overvoltage, undervoltage, overcurrent, short-circuit, and overtemperature conditions. Pack- and cell-related faults are also handled by firmware-based protections.