LTC4071 Li-Ion/Polymer Shunt Battery Charger System with Low Battery Disconnect

Product Details

The LTC4071 allows simple charging of Li-Ion/Polymer batteries from very low current, intermittent or continuous charging sources. A near-zero current low battery latching disconnect function protects even the lowest capacity batteries from deep discharge and potentially irreparable damage. The 550nA to 50mA operating current makes charging possible from previously unusable sources. With its low operating current the LTC4071 is well suited to charge low capacity Li-Ion or thin film batteries in energy harvesting applications. The unique architecture of the LTC4071 allows for an extremely simple battery charger solution, requiring just one external resistor.

The LTC4071 offers a pin selectable float voltage with ±1% accuracy. The integrated thermal battery qualifier extends battery lifetime and improves reliability by automatically reducing the battery float voltage at NTC thermistor temperatures above 40°C. The LTC4071 also provides two pin selectable low battery disconnect levels and a high battery status output.

The device is offered in two thermally enhanced packages, a compact low profile (0.75mm) 8-lead (2mm × 3mm) DFN and an 8-lead MSOP package.


  • Low Capacity, Li-Ion/Polymer Battery Back-Up
  • Thin Film Batteries
  • Energy Scavenging/Harvesting
  • Solar Power Systems with Back-Up
  • Memory Back-Up
  • Embedded Automotive

Features and Benefits

  • Charger Plus Pack Protection in One IC
  • Low Operating Current (550nA)
  • Near Zero Current (<0.1nA) Low Battery Disconnect Function to Protect Batteries from Over-Discharge
  • Pin Selectable Low Battery Disconnect Level: 2.7V or 3.2V
  • 1% Float Voltage Accuracy Over Temperature
  • 50mA Maximum Internal Shunt Current
  • Pin Selectable Float Voltage Options: 4.0V, 4.1V, 4.2V
  • Ultralow Power Pulsed NTC Float Conditioning for Li-Ion/Polymer Protection
  • Suitable for Intermittent, Continuous and Very Low Power Charging Sources
  • High Battery Status Output
  • Thermally Enhanced, Low Profile (0.75mm) 8-lead (2mm × 3mm) DFN and MSOP Packages