MOTF4055-A6 is an excellent single-cell lithium-ion battery constant current/constant voltage linear charging IC. It can be powered by USB power or adapter power. It has built-in power MOSFET, detection resistor and isolation diode. It has thermal regulation function, which can maximize the charging rate without the risk of overheating. The charging cut-off voltage is 4.2V, and the charging current can be set by an external resistor. When the charging current drops to 1/10 of the set value, the chip will automatically terminate the charging cycle. In addition, there are battery temperature monitoring, undervoltage lockout, automatic recharging and other functions.