LT3652 - Power Tracking 2A Battery Charger for Solar Power

The LT®3652 is a complete monolithic step-down battery charger that operates over a 4.95V to 32V input voltage range. The LT3652 provides a constant-current/ constant-voltage charge characteristic, with maximum charge current externally programmable up to 2A. The charger employs a 3.3V float voltage feedback reference, so any desired battery float voltage up to 14.4V can be programmed with a resistor divider.

The LT3652 employs an input voltage regulation loop, which reduces charge current if the input voltage falls below a programmed level, set with a resistor divider. When the LT3652 is powered by a solar panel, the input regulation loop is used to maintain the panel at peak output power.

The LT3652 can be configured to terminate charging when charge current falls below 1/10 of the programmed maximum (C/10). Once charging is terminated, the LT3652 enters a low-current (85μA) standby mode. An auto-recharge feature starts a new charging cycle if the battery voltage falls 2.5% below the programmed float voltage. The LT3652 also contains a programmable safety timer, used to terminate charging after a desired time is reached. This allows top-off charging at currents less than C/10.

  • Input Supply Voltage Regulation Loop for Peak Power Tracking in (MPPT) Solar Applications
  • Wide Input Voltage Range: 4.95V to 32V (40V Abs Max)
  • Programmable Charge Rate Up to 2A
  • User Selectable Termination: C/10 or On-Board Termination Timer
  • Resistor Programmable Float Voltage Up to 14.4V Accommodates Li-Ion/Polymer, LiFePO4, SLA Chemistries
  • No VIN Blocking Diode Required for Battery Voltages ≤ 4.2V
  • 1MHz Fixed Frequency
  • 0.5% Float Voltage Reference Accuracy
  • 5% Charge Current Accuracy
  • 2.5% C/10 Detection Accuracy
  • Binary-Coded Open-Collector Status Pins
  • Thermally Enhanced 12-Lead 3mm × 3mm DFN andMSE Packages
Typical Application

  • Solar Powered Applications
  • Remote Monitoring Stations
  • LiFePO4 (Lithium Phosphate) Applications
  • Portable Handheld Instruments
  • 12V to 24V Automotive Systems

Order Information
Part NumberPackageTempPrice(1-99)Price (1k)*
LT3652EDD#PBF3x3 DFN-12E$4.36$3.05
LT3652EDD#TRPBF3x3 DFN-12E$3.11
LT3652IDD#PBF3x3 DFN-12I$4.80$3.36
LT3652IDD#TRPBF3x3 DFN-12I$3.42
Demo Boards
Part NumberDescriptionPrice
DC1568ALT3652EDD Demo Board | 11.5V to 32VIN, 2A Buck Battery Charger, MPPC for Solar Power Input$150.00
Reliability Data
Product Selector Card
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