Features: Wide Input Supply Range: 4.7V to 22V 4.2 Version 8.9V to 22V 8.4 Version
High Efficiency Current Mode PWM Controller with 500kHz Switching Frequency
±1% Charge Voltage Accuracy
End-of-Charge Current Detection Output
3 Hour Charge Termination Timer
Constant Switching Frequency for Minimum Noise
±5% Charge Current Accuracy
Low 10µA Reverse Battery Drain Current
Automatic Battery Recharge
Automatic Shutdown When Input Supply is Removed
Automatic Trickle Charging of Low Voltage Batteries
Battery Temperature Sensing and Charge Qualification
Stable with Ceramic Output Capacitor
8-Lead SO and 10-Lead DFN PackagesApplication Portable Computers
Charging Docks
Handheld InstrumentsPinout
SpecificationsSupply Voltage (VCC) .......................................................24V
GATE ........................................................ (VCC 8V) to VCC
BAT, SENSE .................................................... 0.3V to 14V
CHRG, NTC ...................................................... 0.3V to 8V
Operating Temperature Range (Note 4) .. 40°C to 85°C
Storage Temperature Range ................. 65°C to 125°C
Lead Temperature (S8 Package)
(Soldering, 10 sec) ................................................. 300°CDescriptionThe LTC®4002 is a complete battery charger controller for one (4.2V) or two (8.4V) cell lithium-ion batteries. With a 500kHz switching frequency, the LTC4002 provides a small, simple and efficient solution to fast charge Li-Ion batteries from a wide range of supply voltages. An external sense resistor sets the charge current with ±5% accuracy.
An internal resistor divider and precision reference set the final float voltage to 4.2V per cell with ±1% accuracy.
When the input supply is removed, the LTC4002 automatically enters a low current sleep mode, dropping the battery drain current to 10µA. An internal comparator detects the near end-of-charge condition while an internal timer sets the total charge time and terminates the charge cycle. After the charge cycle ends, if the battery voltage drops below 4.05V per cell, a new charge cycle will automatically begin.
The LTC4002 is available in the 8-lead SO and 10-lead DFN packages.
The LTC4002 is designed as one kind of standalone Li-lon switch mode battery charge with a 500kHz switching frequency.It provides a small, simple and efficient solution to fast charge Li-Ion batteries from a wide range of supply voltages.An external sense resistor sets the charge current with ±5% accuracy and is available in the 8-lead SO and 10-lead DFN packages.
The LTC4002 has some features such as:(1)wide input supply range:4.7V to 22V--4.2 version and 8.9V to 22V--8.4 version;(2)high efficiency current mode PWM controller with 500kHz switching frequency;(3)±1% charge voltage accuracy;(4)end-of-charge current detection output;(5)3 hour charge termination timer;(6)constant switching frequency for minimum noise;(7)±5% charge current accuracy;(8)low 10µA reverse battery drain current;(9)automatic battery recharge;(10)automatic shutdown when input supply is removed;(11)automatic trickle charging of low voltage batteries;(12)stable with ceramic output capacitor;(13)8-Lead SO and 10-Lead DFN packages.It can be used in portable computers,charging docks and handheld instruments.
The absolute maximum ratings of the LTC4002 can be summarized as:(1)supply voltage (Vcc):24 V;(2)GATE:(Vcc-8V) to Vcc;(3)BAT:-0.3V to 14 V;(4)operating temperature:40°C to 85°C;(9)lead temperature:300°C;(10)storage temperature range:-65°C to 125°C.If you want to know more information such as the electrical characteristics about the LTC4002,please download the datasheet in www.seekic.com or www.chinaicmart.com .
LTC4002 Data Sheet
