LTC4071 Li-Ion/Polymer Shunt Battery Charger System with Low Battery Disconnect FEATURESDESCRIPTION n Charger Plus Pack Protection in One IC The LTC®4071 allows simple charging of Li-Ion/Polymer n Low Operating Current (550nA) batteries from very low current, intermittent or continuous n Near Zero Current (<0.1nA) Low Battery Disconnect charging sources. A near-zero current low battery latch- Function to Protect Batteries from Over-Discharge ing disconnect function protects even the lowest capacity n Pin Selectable Low Battery Disconnect Level: batteries from deep discharge and potentially irreparable 2.7V or 3.2V damage. The 550nA to 50mA operating current makes n 1% Float Voltage Accuracy Over Temperature charging possible from previously unusable sources. With n 50mA Maximum Internal Shunt Current its low operating current the LTC4071 is well suited to n Pin Selectable Float Voltage Options: 4.0V, 4.1V, 4.2V charge low capacity Li-Ion or thin film batteries in energy n Ultralow Power Pulsed NTC Float Conditioning for harvesting applications. The unique architecture of the Li-Ion/Polymer Protection LTC4071 allows for an extremely simple battery charger n Suitable for Intermittent, Continuous and Very Low solution, requiring just one external resistor. Power Charging Sources The LTC4071 offers a pin selectable float voltage with n High Battery Status Output ±1% accuracy. The integrated thermal battery quali- n Thermally Enhanced, Low Profile (0.75mm) fier extends battery lifetime and improves reliability by 8-Lead (2mm × 3mm) DFN and MSOP Packages automatically reducing the battery float voltage at NTC thermistor temperatures above 40°C. The LTC4071 also provides two pin selectable low battery disconnect levels APPLICATIONS and a high battery status output. n Low Capacity, Li-Ion/Polymer Battery Back-Up n The device is offered in two thermally enhanced packages, Thin Film Batteries n a compact low profile (0.75mm) 8-lead (2mm × 3mm) Energy Scavenging/Harvesting n DFN and an 8-lead MSOP package. Solar Power Systems with Back-Up n Memory Back-Up All registered trademarks and trademarks are the property of their respective owners. n Embedded Automotive TYPICAL APPLICATIONBattery Disconnect ILEAK vs Temperature VIN 100n VBAT = 2.65V RIN 10n TO SYSTEM LOAD: VCC 1n ADJ VCC BAT (A) NTC LTC4071 100p I LEAK 1µF + 10p LBSEL GND Li-Ion 1p 4071 TA01a 0.1p–25 0 25 50 75 100 125 TEMPERATURE (°C) 4071 TA01b Rev. D Document Feedback For more information www.analog.com 1 Document Outline Features Applications Typical Application Description Absolute Maximum Ratings Pin Configuration Order Information Electrical Characteristics Typical Performance Characteristics Pin Functions Block Diagram Operation Applications Information Package Description Revision History Typical Application Related Parts