XT4059 Datasheet | natlinear

Description The XT4059 is a plete constant-current /constant -voltage linear charger for single cell lithium-ion batteries. Its Thin SOT package and low external ponent count make the XT4059 ideally suited for portable applications. Furthermore, the XT4059 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 MOSFET 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, and the charge current can be programmed externally with a single resistor. The XT4059 automatically 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 XT4059 automatically enters a low current state, dropping the battery drain current to less than 1u A. The XT4059 can be put into shutdown mode, reducing the supply current to 25µA. When battery reversed,the internal protected the BAT pin throughout about 0.7m A current from GND.. Other features include charge current monitor, under-voltage lockout, automatic recharge and a status pin to indicate charge termination and the presence of an input voltage. - Typical Application Circuit - Features - Constant-Current/Constant-Voltage - Charges Single Cell Li-Ion Batteries Directly from USB Port - Preset 4.2V Charge Voltage with ±1% Accuracy - Charge Current Monitor Output for Gas Gauging - Automatic Recharge - Charge Status Output Pin - 1/10 Charge Termination - 25u A Supply Current in Shutdown - 2.4V Trickle Charge Threshold (XT4059) - Soft-Start Limits Inrush Current - Battery reversed protection - Applications - wearable devices - Bluetooth Applications - Package - SOT-553 - SOT23-5L - SOT89-5L RLED PROG C1 330Ω CHRG VBAT C2 RPROG NOTE: C1=4.7 u F,...