LT1513/LT1513-2 SEPIC Constant- or Programmable-Current/ Constant-Voltage Battery Charger DESCRIPTION FEATURES n Charger Input Voltage May Be Higher, Equal to or The LT 1513 is a 500kHz current mode switching regula- Lower Than Battery Voltage tor specially configured to create a constant- or program- n Charges Any Number of Cells Up to 20V mable-current/constant-voltage battery charger. In addition n 1% Voltage Accuracy for Rechargeable Lithium to the usual voltage feedback node, it has a current sense Batteries feedback circuit for accurately controlling output current n 100mV Current Sense Voltage for High Efficiency of a flyback or SEPIC (Single-Ended Primary Inductance (LT1513) Converter) topology charger. These topologies allow the n 0mV Current Sense Voltage for Easy Current current sense circuit to be ground referred and completely Programming (LT1513-2) separated from the battery itself, simplifying battery switch- n Battery Can Be Directly Grounded ing and system grounding problems. In addition, these n 500kHz Switching Frequency Minimizes topologies allow charging even when the input voltage is Inductor Size lower than the battery voltage. The LT1513 can also drive n Charging Current Easily Programmable or Shut Down a CCFL Royer converter with high efficiency in floating or grounded mode. U APPLICATIONS Maximum switch current on the LT1513 is 3A. This allows n battery charging currents up to 2A for a single lithium-ion Charging of NiCd, NiMH, Lead-Acid or Lithium cell. Accuracy of 1% in constant-voltage mode is perfect Rechargeable Cells n for lithium battery applications. Charging current can be Precision Current Limited Power Supply n easily programmed for all battery types. Constant-Voltage/Constant-Current Supply n Transducer Excitation , LTC and LT are registered trademarks of Linear Technology Corporation. n Universal Input CCFL Driver TYPICAL APPLICATION Maximum Charging Current WALL L1A* 2.4 ADAPTER C2** 7 C3 INPUT + 4.7m F 2.2 D1 SINGLE Li-Ion CELL 22m F 5 V IN (4.1V) V 25V SW 2.0 1.25A 1.8 CHARGE DOUBLE Li-Ion L1B* LT1513 R1 CELL (8.2V) SYNC 1.6 2 6 AND/OR S/S V FB 1.4 SHUTDOWN C1 SHUTDOWN GND V I + C FB 12V R4 R2 22m F 1.2 4 TAB13 39W 25V 16V 2 R5 1.0 270W 20V C4 R3 0.8 C5 0.22m F 0.08W 0.1m F BATTERY 0.6 VOLTAGE LT1513 TA01 0.4 * L1A, L1B ARE TWO 10m H WINDINGS ON A 05 10 15 20 25 30 COMMON CORE: COILTRONICS CTX10-4 INPUT VOLTAGE (V) ** CERAMIC MARCON THCR40EIE475Z OR TOKIN 1E475ZY5U-C304 INDUCTOR = 10m H MBRD340 OR MBRS340T3. MBRD340 HAS 5A TYPICAL ACTUAL PROGRAMMED CHARGING CURRENT WILL BE LEAKAGE, MBRS340T3 50A TYPICAL INDEPENDENT OF INPUT VOLTAGE IF IT DOES NOT EXCEED VALUES SHOWN LT1513 TA02 Figure 1. SEPIC Charger with 1.25A Output Current sn1513 1513fas 1 CURRENT (A) U ULT1513/LT1513-2 ABSOLUTEXAI U RATI GS Operating Junction Temperature Range Supply Voltage ....................................................... 30V LT1513C ............................................... 0 C to 125 C Switch Voltage ........................................................ 40V LT1513I ............................................ 40 C to 125 C S/S Pin Voltage ....................................................... 30V Short Circuit ......................................... 0 C to 150 C FB Pin Voltage (Transient, 10ms) ......................... 10V Storage Temperature Range ................ 65 C to 150 C V Pin Current .................................................... 10mA FB I Pin Voltage (Transient, 10ms) ......................... 10V Lead Temperature (Soldering, 10 sec)................. 300 C FB PACKAGE/ORDER I FOR ATIO ORDER PART ORDER PART FRONT VIEW NUMBER NUMBER 7 V IN FRONT VIEW 6 S/S TAB 5 V V SW 7 LT1513CR IN LT1513-2CT7 IS 4 GND S/S 6 GND 3 I LT1513-2CR V LT1513-2IT7 FB 5 SW 2 FB GND 4 LT1513IR 1 V I C 3 FB FB 2 LT1513-2IR R PACKAGE V 1 C 7-LEAD PLASTIC DD T7 PACKAGE T = 125 C, q = 30 C/ W JMAX JA 7-LEAD TO-220 2 WITH PACKAGE SOLDERED TO 0.5INCH COPPER T = 125 C, q = 50 C/ W, q = 4 C/W JMAX JA JC AREA OVER BACKSIDE GROUND PLANE OR INTERNAL POWER PLANE, q CAN VARY FROM 20 C/W TO JA > 40 C/W DEPENDING ON MOUNTING TECHNIQUE Consult factory for Military grade parts. LECTR AL CHARACTERIST E IC ICS V = 5V, V = 0.6V, V = V , I = 0V, V and S/S pins open, unless otherwise noted. IN C FB REF FB SW SYMBOL PARAMETER CONDITIONS MIN TYP MAX UNITS V FB Reference Voltage Measured at FB Pin 1.233 1.245 1.257 V REF V = 0.8V l 1.228 1.245 1.262 V C FB Input Current V = V 300 550 nA FB REF l 600 nA FB Reference Voltage Line Regulation 2.7V V 25V, V = 0.8V l 0.01 0.03 %/V IN C V I Reference Voltage (LT1513) Measured at I Pin 107 100 93 mV IREF FB FB V = 0V, V = 0.8V l 110 100 90 mV FB C I Input Current V = V (Note 2) l 10 25 35 m A FB IFB IREF I Reference Voltage Line Regulation 2.7V V 25V, V = 0.8V l 0.01 0.05 %/V FB IN C I I Voltage Offset (LT1513-2) (Note 3) I = 60m A (Note 4) l 7.5 2.5 12.5 mV FBVOS FB VFB I Input Current V = V l 200 10 0 nA FB IFB IREF V Source Current V = 10mV, V = 1.2V l 700 300 100 m A FB IREF FB g Error Amplifier Transconductance D I = 25m A 1100 1500 1900 m mho m C l 700 2300 m mho Error Amplifier Source Current V = V 150mV, V = 1.5V l 120 200 350 m A FB REF C Error Amplifier Sink Current V = V + 150mV, V = 1.5V l 1400 2400 m A FB REF C sn1513 1513fas 2 U WU U W W W