■ Features
 Programmable charge current up to 1A
 No MOSFET, sense resistor or blocking diode required
 Complete linear charger in small 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, also can be adjusted by FB
 Monitor output charge current
 Automatic recharge
 Charge status output pin
 1/10 charge current termination
 25μA supply current in shutdown
 2.9V trickle charge threshold
 Soft-Start limits inrush current
 Output with protection against anti-irrigation
 Available in SOP-8 Package
■ General Description
The LN2053 is a constant- current / constant- voltage charger circuit for single cell lithium-ion batteries. The device includes an internal power transistor, does not need external current sense resistor and blocking diode in applications. LN2053 requires minimal external components, and meet the USB bus specification, is very suitable for portable applications in the field.
Thermal modulation circuit can control the chip temperature in a safe range when the device power dissipation is relatively large or the ambient temperature is higher. Within a fixed constant charge voltage 4.2V, can also be adjusted by an external resistor. Charge current set by an external resistor.
When the input voltage (AC adapter or USB power supply) power is lost, LN2053 automatically enters a low power sleep mode, and then the battery current consumption is less than 3μA. Built-in protection circuits against irrigation, when the battery voltage is higher than the input voltage, automatically turn off built-in power MOSFET. Other features include low input voltage latch, automatic recharge, the battery temperature protect and charge status / charge status indication functions.LN2053 uses thermally enhanced 8-pin small outline package eOP-8.
■ Applications
 Mobile phones
 Digital cameras
 MP4 player
 Bluetooth applications
 Electronic dictionary