EC49017-Standalone Linear Lithium Battery Charger

General description

EC49017   is   a   complete   constant-current   & constant voltage linear charger for single cell lithium-ion and Lithium-Polymer batteries. Its SOT23 package and low  external  component  count  make  EC49017 ideally suited   for   portable   applications.  thermore,   the EC49017 is  specifically  designed  to  work  within  USB power  specification.    At  the  same  time,  EC49017 can also   be   used   in   the   standalone   lithium-ion   and ithium-polymer battery chargers.No  external  sense  resistor  is  needed,  and  no blocking diode is required due to the internal MOSFET 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 4.22V, and the charge current can be programmed   externally   with   a   single   resistor.The EC49017  automatically  inates  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 EC49017 automatically enters a low current stage, opping the battery drain current to less   than   2uA.      The   EC49017   can   be   put   into hutdown mode, reducing the supply current to 20uA. Other  features  include  charge  current  onitor, undervoltage lockout, automatic recharge and a status pin to indicate charge termination and the presence of an  input voltage.  EC49017 is  intentionally  designed to have slightly  negative  Tempco.  This  provides  extra protection to Lithium battery during charging.


  • Programmable Charge Current Up to 800mA
  • No MOSFET, Sense Resistor or Blocking Diode Required
  • Constant-Current/Constant-Voltage Operation with Thermal Protection to Maximize Charge Rate without Risk of Overheating
  • Charges Single Cell Li-ion Batteries Directly from USB Port
  • Preset 4.22V Charge Voltage with ±1% Accuracy
  • 20μA Supply Current in Shutdown
  • 9V Trickle Charge Threshold
  • Soft-Start Limits Inrush Current
  • Available in 6-Lead SOT23 and SOP-8(Exposed PAD) Packages
  • RoHS Compliant and 100% Lead Pb free


  • Cellular Telephones, PDA, MP3 Players
  • Charging Docks and Cradles
  • Bluetooth Applications

Pin Configurations

Ordering info

Typical Applications circuit