ME4056 General Description
ME4056 is a complete constant-current/constant voltage linear charger for single cell lithium-ion batteries. With a thermally enhanced 8-PIN SOP package on the bottom and low external component count make the ME4056 ideally suited for portable applications. Furthermore the ME4056 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 PMOSFET 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 (ME4056A is 4.34V),and the charge current can be programmed externally with a single resistor. The ME4056 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 ME4056 automatically enters a low current state dropping the battery drain current to less than 2μA.The ME4056 can be put into shutdown mode reducing the supply current to 55μA.
Other features include Battery temperature monitor, under-voltage lockout, automatic recharge and two status pins to indicate charge and charge termination.
ME4056 Features
Protection of battery cell reverse connection
Programmable charge current up to 1A
No MOSFET sense resistor or blocking diode required
Complete linear Charger in SOP8 Package for single Cell Lithium-Ion Batteries.
Constant-Current/Constant-Voltage operation with thermal regulation to maximize Rate Without risk of overheating.
Preset 4.2V (ME4056A is 4.34V) charge voltage with ±1% accuracy
Automatic Recharge
Two Status Indication for Charge status, no battery and battery failure indicators
C/10 charge termination
55μA supply current in shutdown
2.9V trickle current charge threshold
Soft-Start limits inrush current
Battery Temperature Sensing
ME4056 Applications
Cellular Telephones
Digital Still Cameras
MP3 Players
Bluetooth Applications
Portable Devices
USB Bus-Powered Chargers
ME4056 Pin Configuration