LTC4002 Standalone Li-Ion Switch Mode Battery Charger FEATURES DESCRIPTIO Wide Input Supply Range: The LTC 4002 is a complete battery charger controller for 4.7V to 22V 4.2 Version one (4.2V) or two (8.4V) cell lithium-ion batteries. With a 8.9V to 22V 8.4 Version 500kHz switching frequency, the LTC4002 provides a High Efficiency Current Mode PWM Controller with small, simple and efficient solution to fast charge Li-Ion 500kHz Switching Frequency batteries from a wide range of supply voltages. An external 1% Charge Voltage Accuracy sense resistor sets the charge current with 5% accuracy. End-of-Charge Current Detection Output An internal resistor divider and precision reference set the 3 Hour Charge Termination Timer final float voltage to 4.2V per cell with 1% accuracy. Constant Switching Frequency for Minimum Noise When the input supply is removed, the LTC4002 automati- 5% Charge Current Accuracy cally enters a low current sleep mode, dropping the battery Low 10A Reverse Battery Drain Current drain current to 10A. An internal comparator detects the Automatic Battery Recharge near end-of-charge condition while an internal timer sets Automatic Shutdown When Input Supply is Removed the total charge time and terminates the charge cycle. After Automatic Trickle Charging of Low Voltage Batteries the charge cycle ends, if the battery voltage drops below Battery Temperature Sensing and Charge 4.05V per cell, a new charge cycle will automatically begin. Qualification The LTC4002 is available in the 8-lead SO and 10-lead DFN Stable with Ceramic Output Capacitor packages. 8-Lead SO and 10-Lead DFN Packages , LTC and LT are registered trademarks of Linear Technology Corporation. U All other trademarks are the property of their respective owners. APPLICATIO S Portable Computers Charging Docks Handheld Instruments TYPICAL APPLICATIO 1.5A Single Cell Li-Ion Battery Charger Efficiency vs Input Voltage V IN 100 (CURVES INCLUDE 5V TO 22V INPUT DIODE) 90 V = 4V BAT 0.1F 10F V CC BAT GATE V = 3.8V 80 BAT 2k LTC4002ES8-4.2 CHARGE 6.8H 70 STATUS CHRG SENSE 68m 60 COMP BAT 5 10 15 20 25 NTC GND INPUT VOLTAGE (V) + 0.47F Li-Ion 22F 4002 TA02 BATTERY 2.2k 10k 4002 TA01 T NTC NTC: DALE NTHS-1206N02 4002f 1 EFFICIENCY (%) U ULTC4002 ABSOLUTE AXI U RATI GS (Note 1) Supply Voltage (V ) .............................................. 24V Operating Temperature Range (Note 4) .. 40C to 85C CC GATE .................................................. (V 8V) to V Storage Temperature Range ................. 65C to 125C CC CC BAT, SENSE .............................................. 0.3V to 14V Lead Temperature (S8 Package) CHRG, NTC ................................................. 0.3V to 8V (Soldering, 10 sec) ........................................... 300C UUW PACKAGE/ORDER I FOR ATIO TOP VIEW ORDER PART ORDER PART TOP VIEW NUMBER NUMBER COMP 1 10 NC COMP 1 8 NTC V 2 9 NTC CC LTC4002EDD-4.2 LTC4002ES8-4.2 GATE 3 11 8 SENSE V 2 7 SENSE CC 4 7 LTC4002EDD-8.4 LTC4002ES8-8.4 PGND BAT GATE 3 6 BAT SGND 5 6 CHRG GND 4 5 CHRG DD PART MARKING S8 PART MARKING DD PACKAGE S8 PACKAGE 10-LEAD (3mm 3mm) PLASTIC DFN 8-LEAD PLASTIC SO LAGG 400242 T = 125C, = 43C/W JMAX JA T = 125C, = 110C/W JMAX JA EXPOSED PAD IS GND (PIN 11) LBGY 400284 MUST BE SOLDERED TO PCB Consult LTC Marketing for parts specified with wider operating temperature ranges. ELECTRICAL CHARACTERISTICS (LTC4002-4.2) The denotes the specifications which apply over the full operating temperature range, otherwise specifications are at T = 25C. V = 10V unless otherwise noted. A CC SYMBOL PARAMETER CONDITIONS MIN TYP MAX UNITS DC Characteristics V V Supply Voltage 4.7 22 V CC CC I V Supply Current Current Mode 3 5 mA CC CC Shutdown Mode 3 5 mA Sleep Mode 10 20 A V Battery Regulated Float Voltage 5V V 22V (Note 2) 4.168 4.2 4.232 V BAT(FLT) CC 4.158 4.242 V V Constant Current Sense Voltage 3V V 4V (Note 3) 0C T 85C 93 100 107 mV SNS(CHG) BAT A 40C T 85C 90 110 mV A V Trickle Current Sense Voltage V = 0V (Note 3) 5 10 15 mV SNS(TRKL) BAT V Trickle Charge Threshold Voltage V Rising 2.75 2.9 3.05 V TRKL BAT V V Undervoltage Lockout Threshold Voltage V Rising 3.9 4.2 4.5 V UV CC CC V V Undervoltage Lockout Hysteresis Voltage 200 mV UV CC V Manual Shutdown Threshold Voltage COMP Pin Falling 200 360 500 mV MSD V Automatic Shutdown Threshold Voltage V V 250 mV ASD CC BAT I COMP Pin Output Current V = 1.2V 100 A COMP COMP I CHRG Pin Weak Pull-Down Current V = 1V 15 25 35 A CHRG CHRG V CHRG Pin Output Low Voltage I = 1mA 0.15 0.3 V CHRG CHRG R End-of-Charge Ratio V /V 10 25 32 % EOC SNS(EOC) SNS(CHG) t Charge Time Accuracy 10 % TIMER 4002f 2 U WWW