General Description

The LP28056 is a complete constant-current/ constant-voltage linear charger for single cell lithium-ion  batteries.  Its  ESOP-8  package  and  low external component count make the LP28056 ideally suited for portable applications. 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 RISET rammed externally with a single resistor. The LP28056 automatically terminates the charge cycle when the charge current drops to 1/10th the RISET rammed value after the final float voltage is reached. When the input supply is removed, the LP28056 automatically enters a low current state, dropping the battery drain current to less than 1µA. The LP28056 can be put into shutdown mode, reducing the supply current to 1µA.

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.