LT3651-4.2 - Monolithic 4A High Voltage Li-Ion Battery Charger
Features
- Please Contact Marketing for Additional Information
- Wide Input Voltage Range: 4.8V to 32V
(40V Absolute Maximum) - Programmable Charge Current Up to 4A
- Selectable C/10 or Onboard Timer Termination
- Dynamic Charge Rate Programming/Soft-Start
- Programmable Input Current Limit
- 0.5% Float Voltage Accuracy
- 7.5% Charge Current Accuracy
- 4% C/10 Detection Accuracy
- NTC Resistor Temperature Monitor
- Auto-Recharge at 97.5% Float Voltage
- Auto-Precondition <70% Float Voltage
- Bad Battery Detection with Auto-Reset
- Average Current Mode, Synchronous Switcher
- User Programmable Frequency
- Low Profile (0.75mm) 5mm × 6mm 36-Pin QFN Package
Typical Application
Description
The LT3651 is a 4A Li-Ion/Polymer battery charger that operates over a 4.8V to 32V input voltage range. An efficient monolithic average current mode synchronous switching regulator provides constant current, constant voltage charging with programmable maximum charge current. A charging cycle starts with battery insertion or when the battery voltage drops 2.5% below the float voltage. Charger termination is selectable as either charge current or internal safety timer timeout. Charge current termination occurs when the charge current falls to one tenth the programmed maximum current (C/10). Timer based termination is typically set to three hours and is user programmable (charging continues below C/10 until timeout). Once charging is terminated, the LT3651 supply current drops to 85μA into a standby mode.
The LT3651 offers several safety features. A discharged battery is preconditioned with a small trickle charge and generates a signal if unresponsive. A thermistor monitors battery temperature, halting charging if out of range. Excessive die temperature reduces charge current. Charge current is also reduced to maintain constant input current to prevent excessive input loading.
The LT3651 is available in a 5mm × 6mm 36-pin QFN package.
Packaging
For complete and up to date package information and drawings, please refer to our packaging page
QFN-36
Order Info
- Part numbers ending in PBF are lead free. Please contact LTC marketing for information on lead based finish parts.
- 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
Demo Boards
Linear Technology demo boards are offered free of charge to qualified customers. Contact your local sales office or distributor to request 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.Click here to view our complete list of demo boards
Applications
- Industrial Handheld Instruments
- 12V to 24V Automotive and Heavy Equipment
- Desktop Cradle Chargers
- Notebook Computers
Simulate
LTspice IV is a powerful, fast and free simulation tool, schematic capture and waveform viewer with enhancements and models for improving the simulation of switching regulators. To download LTspice IV and other FREE simulation tools, please visit our Design Simulation page.
Technical Support
- For immediate technical assistance, contact your local sales office or distributor or call 1-800-4-LINEAR (US customers only) or 408-432-1900.
- For less urgent requests, please complete our Technical Support Request Form. Please allow 2-3 business days for reply.