The battery pack balancer is a fault protection controller, suitable for transformer-based two-way active charge balancing of multi-cell battery packs. The battery pack balancer integrates all relevant gate drive circuits, high-precision battery sensing, fault detection circuits and a robust serial interface with a built-in watchdog timer.

Each battery pack balancer can use an input common-mode voltage of up to 36V to charge balance up to 6 batteries connected in series. The charge from any selected battery can be transferred back and forth between itself and 12 or more adjacent batteries with high efficiency. A unique level-shifting SPI compatible serial interface can complete the series connection of multiple battery pack balancers without using optocouplers or isolators, thereby realizing the charge balance of each battery in a long series of batteries.

Features of battery pack balancer:
· Two-way synchronous flyback balance of up to 6 series lithium-ion or lifepo4 batteries can be realized;
· Two-way architecture minimizes balance time and power dissipation;
· The charge transfer efficiency is as high as 92%;
· Stackable architecture can be used in 》1000V system;
· Use a simple dual-winding transformer;
· 1MHz daisy-chain serial interface with 4-bit CRC packet error checking;
· High noise margin serial communication;
· Numerous fault protection functions;
· 48-pin QFN package and LQFP package with exposed pads.