Description:

The Slkor®4054 is a complete constant-current/constant-voltage linear charger for single cell lithium-ion batteries. Its SOP package and low external component count make the SL4054 ideally suited for portable applications. Furthermore, the SL4054 can work within USB and wall adapter. No blocking diode is required due to the internal PMOSFET architecture and have prevent to negative Charge Current Circuit. 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, and the charge current can be programmed externally with a single resistor. The SL4054 automatically terminates the charge cycle when the charge current drops to 1/10th the programmed value after the final float voltage is reached. When removing input power automatically puts the SL4054 into a low current mode to reduce the battery's leakage current to below 2uA, and the shutdown mode reduces supply current to 45µA. SL4054 Other features include current monitor, under voltage lockout, automatic recharge and two status pin to indicate charge termination and the presence of an input voltage. The Slkor® SL4054 is available in a SOT23-5 (ThinSOT^TM) package.

Characteristics:

● The programmable charging current as high as 500mA;

● In no need of extemal MOSFET,sense resistors or backward diodes;

● Constant current/constant voltage mode operation,with the function of thermal protection;

● Charging for lithium batteries through the USB port:

● Preset charging voltage with the accuracy of 1%;

● The current of 20uA in the standby mode:

● The trickle charging voltage of 2.9V

● The limitation of the surge current with soft start

● The SOT23-5 package

Applications: 
USB-Powered Charging, Handheld Computers, MP3 Players, Bluetooth Headphones, Digital Cameras, Cellular Telephones, PDA.