LTC4059A Datasheet | Linear Technology

LTC4059/LTC4059A 900m A Linear Li-Ion Battery Chargers with Thermal Regulation in 2 × 2 DFN Features DESCRIPTIO - Programmable Charge Current Up to 900m A - Charge Current Monitor Output for Charge Termination - Constant-Current/Constant-Voltage Operation with Thermal Regulation to Maximize Charging Rate Without Risk of Overheating - Constant-Current Source Mode for Charging Nickel Batteries (LTC4059 Only) - ACPR Pin Indicates Presence of Input Supply (LTC4059A Only) - No External MOSFET, Sense Resistor or Blocking Diode Required - Operating Supply Voltage from 3.75V to 8V - Charges Single Cell Li-Ion Batteries Directly from USB Port - Preset 4.2V Charge Voltage with 0.6% Accuracy - 10µA Supply Current in Shutdown Mode - Tiny 6-Lead (2mm × 2mm) DFN Package U APPLICATIO S - Wireless PDAs - Cellular Phones - Portable Electronics - Wireless Headsets - Digital Cameras The LTC®4059/LTC4059A are constant-current/constantvoltage linear chargers for single cell lithium-ion batteries. Their 2mm × 2mm DFN package and low external ponent count make these chargers especially well suited for portable applications. Furthermore, they are designed to work within USB power specifications. No external sense resistor, MOSFET or blocking diode is required. Thermal feedback regulates the charge current to limit the die temperature during high power operation or high ambient thermal conditions. The charge voltage is fixed at 4.2V and the charge current is programmable. When the input supply (wall adapter or USB supply) is removed, the LTC4059/LTC4059A automatically enter a low current state, dropping the battery current drain to less than 1µA. With power applied, they can be put into shutdown mode, reducing the supply current to 10µA. The LTC4059A Features an open-drain status pin to indicate the presence of an input voltage. The LTC4059 can be used as a constant-current source to charge Nickel cells. Other Features include undervoltage lockout protection and a current...