ME4057 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 ME4057
ideally suited for portable applications. Furthermore the ME4057 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,and the charge current can be programmed
externally with a single resistor. The ME4057 automatically terminates the charge cycle when the charge current drops
to 1/10 th the programmed value after the final float voltage is reached.
When the input supply (wall adapter or USB supply) is removed the ME4057 automatically enters a low current
state dropping the battery drain current to less than 2μA.The ME4057 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.
Applications
Typical charge cycle（1000mAh battery）
●Cellular Telephones
●Digital Still Cameras
●MP3 Players
●Bluetooth Applications
●Portable Devices
●USB Bus-Powered Chargers
●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 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
● Available in SOP8-PP package
