The FM5057 is a battery protection IC manufactured by Fuman. It is a RoHS-compliant, 5-pin SOT89 device, built for use in lithium-ion battery applications. It features a wide range of protection functions, such as over-charge protection, over-discharge protection, over-current protection, short-circuit protection, and reverse polarity protection, all of which are adjustable. The IC also has on-chip auto-balancing, delay time, and enable/disable functions, and provides a variety of alarm output options. The FM5057 has a temperature monitor that enables accurate monitoring of the battery's charge and discharge processes. It is capable of delivering up to 10A current and has a wide input voltage range from 4.2V to 30V.