Description

The LP4054 is a complete constant-current/constantvoltage

linear charger for single cell lithium-ion batteries.

Its ThinSOT package and low external component

count make the LP4054 ideally suited for portable

applications. Furthermore, the LP4054 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

LP4054 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 LP4054 automatically enters a low current state,

dropping the battery drain current to less than 2μA. The

LP4054 can be put into shutdown mode, reducing he

supply current to 25μA.Other features include charge

current monitor, undervoltage lockout, automatic

recharge and a status pin to indicate charge termination

and the presence of an input voltage.

Features

Programmable Charge Current Up to 800mA

No MOSFET, Sense Resistor or Blocking Diode

Required

Complete Linear Charger in ThinSOT

Package for

Single Cell Lithium-ion Batteries

Constant-Current/Constant-Voltage Operation

with Thermal Regulation to Maximize Charge

Rate Without Risk of Overheating

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

Soft-Start Limits Inrush Current

Available in 5-Lead SOT-23 Package

2.9V Trickle Charge Threshold

C/10 Charge Termination

25mA Supply Current in Shutdown

2.9V Trickle Charge Threshold

Applications

Portable Media Players/MP3 players

Cellular and Smart mobile phone

Charging Docks and Cradles

Bluetooth Applications