BATTERY VOLTAGE (V) LTC4057-4.2 Linear Li-Ion Battery Charger with Thermal Regulation in ThinSOT FEATURES DESCRIPTIO n Programmable Charge Current up to 800mA The LTC 4057 is a constant-current/constant-voltage lin- n No External MOSFET, Sense Resistor or Blocking ear charger for single-cell lithium-ion batteries. Its TM Diode Required ThinSOT package and low external component count n Constant-Current/Constant-Voltage Operation with make the LTC4057 especially well suited for portable Thermal Regulation Maximizes Charge Rate applications. Furthermore, the LTC4057 is specifically Without Risk of Overheating* designed to work within USB power specifications. n Charges Single Cell Li-Ion Batteries Directly from No external sense resistor is needed and no blocking diode USB Port is required due to the internal MOSFET architecture. n Preset 4.2V Charge Voltage with 1% Accuracy Thermal feedback prevents overheating by regulating the n Current Monitor Pin for Charge Termination charge current to limit the die temperature during high n 25A Supply Current in Shutdown Mode power operation or high ambient temperature conditions. n Low Battery Charge Conditioning (Trickle Charging) The charge voltage is preset at 4.2V and the charge current n Soft-Start Limits Inrush Current can be programmed externally with a single resistor. n Available in a Low Profile (1mm) SOT-23 Package U When the input supply (wall adapter or USB supply) is APPLICATIO S removed, the LTC4057 automatically enters a low current state, dropping the battery drain current to less than 2A. n Wireless PDAs With power applied, the LTC4057 can be put into shut- n Cellular Phones down mode, reducing the supply current to 25A. n Portable Electronics For the standalone version (on-board charge termination) , LTC and LT are registered trademarks of Linear Technology Corporation. ThinSOT is a trademark of Linear Technology Corporation. of the LTC4057, refer to the LTC4054. *U.S. Patent No. 6522118 TYPICAL APPLICATIO Charge Curve (750mAh Battery) 700 4.75 CONSTANT V IN CURRENT 5V 600 4.5 600mA CONSTANT 4 3 CONSTANT POWER V BAT CC VOLTAGE 500 4.25 LTC4057-4.2 400 4.0 1 5 1-CELL + SHDN PROG ON OFF 4.2V Li-Ion GND 300 3.75 BATTERY 2 1F 1.65k 200 3.5 V = 5V CC = 130C/W 4057 TA01a JA 100 3.25 R = 1.65k PROG T = 25C A 0 3.0 0 0.25 0.5 0.75 1.0 1.25 1.5 1.75 2.0 2.25 TIME (HOURS) 4057 TA01b 4057f 1 CHARGE CURRENT (mA) U ULTC4057-4.2 UUW ABSOLUTE AXI U RATI GS PACKAGE/ORDER I FOR ATIO (Note 1) ORDER PART Input Supply Voltage (V ) ........................0.3V to 10V CC NUMBER PROG.............................................. 0.3V to V + 0.3V CC TOP VIEW BAT ..............................................................0.3V to 7V LTC4057ES5-4.2 SHDN 1 5 PROG SHDN.........................................................0.3V to 10V GND 2 BAT Short Circuit Duration ...........................Continuous BAT 3 4 V S5 PART CC BAT Pin Current .................................................. 800mA MARKING S5 PACKAGE PROG Pin Current ................................................ 800A 5-LEAD PLASTIC SOT-23 LTAEW Junction Temperature........................................... 125C T = 125C, ( = 100C/W TO 150C/W JMAX JA DEPENDING ON PC BOARD LAYOUT) Operating Ambient Temperature Range (NOTE 3) (Note 2) .............................................. 40C to 85C Storage Temperature Range ................. 65C to 125C Consult LTC Marketing for parts specified with wider operating temperature ranges. Lead Temperature (Soldering, 10 sec).................. 300C ELECTRICAL CHARACTERISTICS The l denotes the specifications which apply over the full operating temperature range, otherwise specifications are at T = 25C. V = 5V A CC SYMBOL PARAMETER CONDITIONS MIN TYP MAX UNITS V Input Supply Voltage l 4.25 6.5 V CC I Input Supply Current I = 0mA, R = 2k l 200 600 A CC BAT PROG Shutdown Mode (SHDN = 0V, l 50 A V < V , or V < V ) CC BAT CC UV V Regulated Output (Float) Voltage I = 40mA, 0C < T < 85C 4.158 4.2 4.242 V FLOAT BAT A I BAT Pin Charge Current R = 10k Current Mode l 93 100 107 mA BAT PROG R = 2k Current Mode l 465 500 535 mA PROG Shutdown Mode (SHDN = 0V) 1 2 A Sleep Mode (V = 0V) 1 2 A CC I Trickle Charge Current V < 2.9V R = 2k (I = 500mA) l 20 50 70 mA TRIKL BAT PROG CHG V Trickle Charge Threshold Voltage R = 10k V Rising 2.8 2.9 3.0 V TRIKL PROG BAT Hysteresis 60 80 110 mV V V Undervoltage Lockout Voltage From Low to High l 3.7 3.8 3.9 V UV CC Hysteresis l 150 200 300 mV V V - V Lockout Threshold Voltage V from Low to High 70 100 150 mV ASD CC BAT CC V from High to Low 5 30 70 mV CC V PROG Pin Voltage R = 10k Current Mode l 0.93 1.0 1.07 V PROG PROG V SHDN Pin Input Low Voltage 0.4 0.65 V SHDN-IL V SHDN Pin Input High Voltage 0.65 1.0 V SHDN-IH I SHDN Pin Input Current V = 5V l 515 A SHDN SHDN T Junction Temperature in 120 C LIM Constant-Temperature Mode R Power FET ON Resistance 600 m ON (Between V and BAT) CC t Soft-Start Time I = 0 to I = 1000V/R 100 s SS BAT BAT PROG 4057f 2 U WWW