LT3650-4.X - High Voltage 2 Amp Monolithic Li-Ion Battery Charger


  • Wide Input Voltage Range: 4.75V to 32V (40V Absolute Maximum)
  • Programmable Charge Current Up to 2A
  • User-Selectable Termination: C/10 or Onboard Termination Timer
  • Dynamic Charge Rate Programming/Soft-Start Pin
  • Programmable Input Current Limit
  • No VIN Blocking Diode Required
  • 1MHz Fixed Frequency
  • Average Current Mode Control
  • 0.5% Float Voltage Accuracy
  • 5% Charge Current Accuracy
  • 2.5% C/10 Detection Accuracy
  • NTC Resistor Temperature Monitor
  • Auto-Recharge at 97.5% Float Voltage
  • Auto-Precondition at <70% Float Voltage
  • Bad Battery Detection with Auto-Reset
  • Binary Coded Open-Collector Status Pins
  • 3mm × 3mm DFN-12 or MSOP-12 Package

Typical Application

LT3650-4.1 Typical Application
LT3650-4.1 Typical Application


The LT3650 is a complete monolithic single-cell Li-Ion/ Polymer battery charger that operates over a 4.75V to 32V input voltage range (7.5V minimum start-up voltage). The LT3650 provides a constant-current/constant-voltage charge characteristic, with maximum charge current externally programmable up to 2A, set using an external current sense resistor. A precondition feature trickle charges a low voltage battery, and bad-battery detection provides a signal and suspends charging if a battery does not respond to preconditioning.

The LT3650 can be configured to terminate charging when charge current falls to C/10, or one-tenth the programmed maximum current. Once charging is terminated, the LT3650 enters a low current (85μA) standby mode. An auto-restart feature starts a new charging cycle if the battery voltage drops 2.5% from the fl oat voltage, or if a new battery is inserted into a charging system.

The LT3650 contains a user-programmable internal safety timer (typically set to a three hour full cycle time). The IC can be configured to use this internal timer if a time-based termination scheme is desired in which charging can continue below C/10 until a desired time is reached.

The LT3650 is available in a low profile (0.75mm) 3mm × 3mm 12-pin DFN and 12-pin MSOP packages.

 Float Voltage
LT3650-4.1 4.1V
LT3650-4.2 4.2V
LT3650-8.2 8.2V
LT3650-8.4 8.4V


CAD Symbols and Footprints: The downloadable Zip file below contains the schematic symbol and PCB footprints.

For complete and up to date package information and drawings, please refer to our packaging page

Part Number Package Code Temp Package
LT3650EDD-4.1#PBF 3x3 DFN-12 DD E 05-08-1725 Yes
LT3650EDD-4.1#TRPBF 3x3 DFN-12 DD E 05-08-1725 Yes
LT3650EDD-4.2#PBF 3x3 DFN-12 DD E 05-08-1725 Yes
LT3650EDD-4.2#TRPBF 3x3 DFN-12 DD E 05-08-1725 Yes
LT3650EMSE-4.1#PBF MS-12E MSE E 05-08-1666 Yes
LT3650EMSE-4.1#TRPBF MS-12E MSE E 05-08-1666 Yes
LT3650EMSE-4.2#PBF MS-12E MSE E 05-08-1666 Yes
LT3650EMSE-4.2#TRPBF MS-12E MSE E 05-08-1666 Yes
LT3650IDD-4.1#PBF 3x3 DFN-12 DD I 05-08-1725 Yes
LT3650IDD-4.1#TRPBF 3x3 DFN-12 DD I 05-08-1725 Yes
LT3650IDD-4.2#PBF 3x3 DFN-12 DD I 05-08-1725 Yes
LT3650IDD-4.2#TRPBF 3x3 DFN-12 DD I 05-08-1725 Yes
LT3650IMSE-4.1#PBF MS-12E MSE I 05-08-1666 Yes
LT3650IMSE-4.1#TRPBF MS-12E MSE I 05-08-1666 Yes
LT3650IMSE-4.2#PBF MS-12E MSE I 05-08-1666 Yes
LT3650IMSE-4.2#TRPBF MS-12E MSE I 05-08-1666 Yes

LT3650-4.1 Package Drawing
LT3650-4.1 Package Drawing

Order Info

  • Part numbers ending in PBF are lead free. Solder plated terminal finish (SnPb) versions are non-standard and special terms and conditions and pricing applies if available. Please contact LTC marketing for information.
  • Part numbers containing TR or TRM are shipped in tape and reel or 500 unit mini tape and reel, respectively
  • Please refer to our general ordering information or the product datasheet for more details

Package Variations and Pricing

Part Number Package Temp Price
LT3650EDD-4.1#PBF 3x3 DFN-12 E $4.00 $2.80 Yes
LT3650EDD-4.1#TRPBF 3x3 DFN-12 E $2.86 Yes
LT3650EDD-4.2#PBF 3x3 DFN-12 E $4.00 $2.80 Yes
LT3650EDD-4.2#TRPBF 3x3 DFN-12 E $2.86 Yes
LT3650EMSE-4.1#PBF MS-12E E $4.00 $2.80 Yes
LT3650EMSE-4.1#TRPBF MS-12E E $2.86 Yes
LT3650EMSE-4.2#PBF MS-12E E $4.00 $2.80 Yes
LT3650EMSE-4.2#TRPBF MS-12E E $2.86 Yes
LT3650IDD-4.1#PBF 3x3 DFN-12 I $4.60 $3.22 Yes
LT3650IDD-4.1#TRPBF 3x3 DFN-12 I $3.28 Yes
LT3650IDD-4.2#PBF 3x3 DFN-12 I $4.60 $3.22 Yes
LT3650IDD-4.2#TRPBF 3x3 DFN-12 I $3.28 Yes
LT3650IMSE-4.1#PBF MS-12E I $4.60 $3.22 Yes
LT3650IMSE-4.1#TRPBF MS-12E I $3.28 Yes
LT3650IMSE-4.2#PBF MS-12E I $4.60 $3.22 Yes
LT3650IMSE-4.2#TRPBF MS-12E I $3.28 Yes
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* The USA list pricing shown is for BUDGETARY USE ONLY, shown in United States dollars (FOB USA per unit for the stated volume), and is subject to change. International prices may differ due to local duties, taxes, fees and exchange rates. For volume-specific price or delivery quotes, please contact your local Linear Technology sales office or authorized distributor.

Demo Boards

Linear Technology offers many demo boards free of charge to qualified customers. Contact your local sales office or distributor to inquire about a demo board. Certain demo boards are also available for sale via credit card on this website. Demo boards are for evaluation purposes only. It remains the customer’s responsibility to verify proper and reliable operation in the actual end application.

Part Number Description Price Documentation
DC1229B-A LT3650EDD-4.2 Demo Board | 7.5V ≤ VIN ≤ 32V, 2A Monolithic Li-Ion Battery Charger $150.00
DC1229B-B LT3650EDD-4.1 Demo Board | 7.5V ≤ VIN ≤ 32V, 2A Monolithic Li-Ion Battery Charger $150.00
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Click here to view our complete list of demo boards


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  • Desktop Cradle Chargers
  • Notebook Computers

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