原装ME4057系列锂电充电IC 充电电流可达到1A

　　ME4057 is a complete constant-current/constant

　　voltage linear charger for single cell lithium-ion batteries.With a thermally enhanced 8-PIN SOP package on the

　　bottom and low external component count make the

　　ME4057 ideally suited for portable applications.

　　Furthermore the ME4057 is specifically designed to work

　　within USB power specifications.No external sense resistor is needed and no blocking

　　diode is required due to the internal PMOSFET

　　architecture .Thermal feedback regulates the charge

　　current to limit the die temperature during high power

　　operation or high ambient temperature .The charge voltage

　　is fixed at 4.2V / 4.34V， and the charge current can be

　　programmed externally with a single resistor. The ME4057automatically terminates the charge cycle when the charge

　　current drops to 1/10th the programmed value after the final

　　float voltage is reached.When the input supply （wall adapter or USB supply） is

　　removed the ME4057 automatically enters a low current

　　state dropping the battery drain current to less than

　　2μA.The ME4057 can be put into shutdown mode reducing

　　the supply current to 55μA.Other features include Battery temperature monitor，

　　under-voltage lockout， automatic recharge and two status

　　pins to indicate charge and charge terminatio