Datasheet LT3651-8.2, LT3651-8.4 (Analog Devices)
| Manufacturer | Analog Devices |
| Description | Monolithic 4A High Voltage 2-Cell Li-Ion Battery Charger |
| Pages / Page | 24 / 1 — FEATURES. DESCRIPTION. Wide Input Voltage Range: 9V to 32V. (40V Absolute … |
| File Format / Size | PDF / 354 Kb |
| Document Language | English |
FEATURES. DESCRIPTION. Wide Input Voltage Range: 9V to 32V. (40V Absolute Maximum). Programmable Charge Current Up to 4A
Model Line for this Datasheet
Text Version of Document
LT3651-8.2/LT3651-8.4 Monolithic 4A High Voltage 2-Cell Li-Ion Battery Charger
FEATURES DESCRIPTION
n
Wide Input Voltage Range: 9V to 32V
The LT®3651-8.2/LT3651-8.4 are 2-cell, 4A Li-Ion/Poly-
(40V Absolute Maximum)
mer battery chargers that operate over a 9V to 32V input n
Programmable Charge Current Up to 4A
voltage range. An efficient monolithic average current n
Selectable C/10 or Onboard Timer Termination
mode synchronous switching regulator provides constant n
Dynamic Charge Rate Programming/Soft-Start
current, constant voltage charging with programmable n
Programmable Input Current Limit
maximum charge current. A charging cycle starts with n ±0.5% Float Voltage Accuracy battery insertion or when the battery voltage drops 2.5% n ±7.5% Charge Current Accuracy below the float voltage. Charger termination is selectable n ±4% C/10 Detection Accuracy as either charge current or internal safety timer timeout. n NTC Resistor Temperature Monitor Charge current termination occurs when the charge cur- n Auto-Recharge at 97.5% Float Voltage rent falls to one-tenth the programmed maximum current n Auto-Precondition at <70% Float Voltage (C/10). Timer based termination is typically set to three n Bad Battery Detection with Auto-Reset hours and is user programmable (charging continues n Average Current Mode, Synchronous Switcher below C/10 until timeout). Once charging is terminated, n User Programmable Frequency the LT3651-8.2/LT3651-8.4 supply current drops to 85µA n Low Profile (0.75mm) 5mm × 6mm 36-Lead into a standby mode. QFN Package The LT3651-8.2/LT3651-8.4 offer several safety features.
APPLICATIONS
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 n Industrial Handheld Instruments range. Excessive die temperature reduces charge current. n 12V to 24V Automotive and Heavy Equipment Charge current is also reduced to maintain constant input n Desktop Cradle Chargers current to prevent excessive input loading. n Notebook Computers L, LT, LTC, LTM, Linear Technology and the Linear logo are registered trademarks of Linear The LT3651-8.2/LT3651-8.4 are available in a 5mm × Technology Corporation. All other trademarks are the property of their respective owners. 6mm 36-lead QFN package.
TYPICAL APPLICATION 12V to 32V 2-Cell 4A Charger Efficiency, Power Loss vs VIN
TO 91 5.0 VIN SYSTEM 12V TO 32V VBAT = 7.8V 22µF LOAD EFFICIENCY 100k I 10V BAT = 4A CLP CLN Si7611DN VIN 90 4.5 SHDN SW POWER LOSS (W) 10k 1µF LT3651-8.2/LT3651-8.4 ACPR BOOST 10µH WÜRTH 74477010 89 4.0 CMPSH1-4 FAULT CHRG SENSE EFFICIENCY (%) RT 24mΩ 88 3.5 301k BAT + POWER LOSS TIMER NTC 100µF 2-CELL Li-Ion ILIM RNG/SS GND BATTERY 87 3.0 10 15 20 25 30 35 365188284 TA01a VIN (V) 36518284 TA01b 36518284fa For more information www.linear.com/LT3651-8.2 1 Document Outline Features Applications Description Typical Application Absolute Maximum Ratings Pin Configuration Order Information Electrical Characteristics Typical Performance Characteristics Pin Functions Block Diagram Operation Applications Information Typical Applications Typical Application Related Parts
FEATURES DESCRIPTION
n
Wide Input Voltage Range: 9V to 32V
The LT®3651-8.2/LT3651-8.4 are 2-cell, 4A Li-Ion/Poly-
(40V Absolute Maximum)
mer battery chargers that operate over a 9V to 32V input n
Programmable Charge Current Up to 4A
voltage range. An efficient monolithic average current n
Selectable C/10 or Onboard Timer Termination
mode synchronous switching regulator provides constant n
Dynamic Charge Rate Programming/Soft-Start
current, constant voltage charging with programmable n
Programmable Input Current Limit
maximum charge current. A charging cycle starts with n ±0.5% Float Voltage Accuracy battery insertion or when the battery voltage drops 2.5% n ±7.5% Charge Current Accuracy below the float voltage. Charger termination is selectable n ±4% C/10 Detection Accuracy as either charge current or internal safety timer timeout. n NTC Resistor Temperature Monitor Charge current termination occurs when the charge cur- n Auto-Recharge at 97.5% Float Voltage rent falls to one-tenth the programmed maximum current n Auto-Precondition at <70% Float Voltage (C/10). Timer based termination is typically set to three n Bad Battery Detection with Auto-Reset hours and is user programmable (charging continues n Average Current Mode, Synchronous Switcher below C/10 until timeout). Once charging is terminated, n User Programmable Frequency the LT3651-8.2/LT3651-8.4 supply current drops to 85µA n Low Profile (0.75mm) 5mm × 6mm 36-Lead into a standby mode. QFN Package The LT3651-8.2/LT3651-8.4 offer several safety features.
APPLICATIONS
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 n Industrial Handheld Instruments range. Excessive die temperature reduces charge current. n 12V to 24V Automotive and Heavy Equipment Charge current is also reduced to maintain constant input n Desktop Cradle Chargers current to prevent excessive input loading. n Notebook Computers L, LT, LTC, LTM, Linear Technology and the Linear logo are registered trademarks of Linear The LT3651-8.2/LT3651-8.4 are available in a 5mm × Technology Corporation. All other trademarks are the property of their respective owners. 6mm 36-lead QFN package.
TYPICAL APPLICATION 12V to 32V 2-Cell 4A Charger Efficiency, Power Loss vs VIN
TO 91 5.0 VIN SYSTEM 12V TO 32V VBAT = 7.8V 22µF LOAD EFFICIENCY 100k I 10V BAT = 4A CLP CLN Si7611DN VIN 90 4.5 SHDN SW POWER LOSS (W) 10k 1µF LT3651-8.2/LT3651-8.4 ACPR BOOST 10µH WÜRTH 74477010 89 4.0 CMPSH1-4 FAULT CHRG SENSE EFFICIENCY (%) RT 24mΩ 88 3.5 301k BAT + POWER LOSS TIMER NTC 100µF 2-CELL Li-Ion ILIM RNG/SS GND BATTERY 87 3.0 10 15 20 25 30 35 365188284 TA01a VIN (V) 36518284 TA01b 36518284fa For more information www.linear.com/LT3651-8.2 1 Document Outline Features Applications Description Typical Application Absolute Maximum Ratings Pin Configuration Order Information Electrical Characteristics Typical Performance Characteristics Pin Functions Block Diagram Operation Applications Information Typical Applications Typical Application Related Parts
