Standalone USB Li-Ion/Polymer Battery Charger in 2mm x 2mm DFN

The LTC4095 is a complete constant-current/constant-voltage linear charger for single-cell lithium-ion/polymer batteries. Its small 2mm × 2mm DFN package and low external component count make the LTC4095 especially well-suited for portable USB power applications.

Up to 950mA of charge current may be programmed via a single resistor from the PROG pin to ground. The HPWR pin allows the charge current to be set at 20% or 100% of its full-scale programmed value. An internal safety timer terminates charge current. The final float voltage is preset to 4.2V and held to a tight 0.5% tolerance. Also featured is an NTC thermistor input to monitor battery temperature while charging, a C/10 current detection output, automatic recharge, bad-battery detection and low-battery trickle charge. A thermal feedback loop regulates the charge current to limit the die temperature during high power operation or high ambient thermal conditions.

The LTC4095 is available in a tiny, low profile (0.75mm) 8-lead 2mm × 2mm DFN package.

Applications

* PDAs

* Media Players

* Cellular Phones

* Other Portable Electronics

* Full-Featured Standalone USB Li-Ion/Polymer Battery Charger

* 100mA to 950mA Programmable Charge Current

* C/10 Charge Current Detection Output

* Internal Safety Timer Termination

* NTC Thermistor Input for Temperature Qualified Charging

* Preset 4.2V Float Voltage with 0.5% Accuracy

* Constant-Current/Constant-Voltage Operation with Thermal Feedback

* Charge Current Monitor Output for Gas Gauging

* Automatic Recharge

* Bad-Battery Detection

* 8.5µA Input Supply Current in Suspend Mode

* Tiny 8-Lead (2mm × 2mm) DFN Package