描述 Description

The LP28057A is a complete constant-current/constant- voltage linear charger for single cell lithium-ion batteries. Its ESOP8 package and low external component count make the LP28057A ideally suited for portable applications. Furthermore, the LP28057A 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 LP28057A automatically terminates the charge cycle when the charge current drops to 1C/10th the programmed value after the final float voltage is reached. When the input supply (wall adapter or USB supply) is removed, the LP28057A automatically enters a low current state, dropping the battery drain current to less than 1μA. Other features include charge current monitor, automatic recharge and a status pin to indicate charge termination and the presence of an input voltage.

特性 Features

·? Protection of Reverse Connection of Battery
·? Programmable Charge Current Up to 1000mA
·? No MOSFET, Sense Resistor or Blocking Diode Required
·? Constant-Current/Constant-Voltage Operation with
·Thermal Regulation to Maximize Charge Rate Without
·Risk of Overheating
·? 1μA Supply Current in Shutdown
·? Drainage Charge Current Thermal Regulation Status
·Outputs for LED or System Interface
·? Indicates Charge and Full
·? Optional Battery Temperature Monitoring Before and
·During Charge Automatic Sleep Mode for Low-Power
·? Consumption Available in ESOP-8 Package
·? RoHS Compliant and 100% Lead (Pb)-Free

應(yīng)用 Application

·? Portable Media Players/MP3 players
·? Cellular and Smart mobile phone
·? PDA/DSC
·? Bluetooth Applications