POWER LOSS (mW) LTC3539/LTC3539-2 2A, 1MHz/2MHz Synchronous Step-Up DC/DC Converters FEATURES DESCRIPTION n Delivers 3.3V at 900mA From 2 Alkaline/NiMH Cells The LTC 3539/LTC3539-2 are synchronous, 2A step-up n Delivers 5V at 900mA From a Lithium-Polymer DC/DC converters with output disconnect. Synchronous Battery rectification enables high efficiency in the low profile n V Start-Up Voltage: 700mV 2mm 3mm DFN package. Battery life is extended with IN n 1.5V to 5.25V V Range a 700mV start-up voltage and operation down to 500mV OUT n Up to 94% Efficiency once started. n V > V Operation IN OUT A switching frequency of 1MHz (LTC3539) or 2MHz n 1.5% Feedback Voltage Tolerance (LTC3539-2) minimizes solution footprint by allowing the n 1MHz (LTC3539) or 2MHz (LTC3539-2) Fixed use of tiny, low profile inductors and ceramic capacitors. Frequency Operation The current mode PWM design is internally compensated, n Output Disconnect reducing external parts count. The LTC3539/LTC3539-2 n Selectable Burst Mode or PWM Operation feature a pin-enabled automatic Burst Mode operation at n 10A Quiescent Current light load conditions. Anti-ring circuitry reduces EMI by n Logic Controlled Shutdown: <1A damping the inductor in discontinuous mode. Additional n Requires Only 6 External Components features include a low shutdown current of under 1A and n Low Profile (2mm 3mm 0.75mm) DFN Package thermal overload protection. APPLICATIONS The LTC3539/LTC3539-2 are offered in a 2mm 3mm 0.75mm DFN package. n Medical Instruments L, LT, LTC, LTM and Burst Mode are registered trademarks and ThinSOT is a trademark of n Portable Bar Code Scanners Linear Technology Corporation. All other trademarks are the property of their respective owners. n Noise Canceling Headphones n Portable GPS Navigation n Handheld PCs TYPICAL APPLICATION Wide V , High Power 3.3V Regulator IN Efficiency and Power Loss vs Load Current 100 1000 4.7H 90 V IN 1.8V TO 3.6V EFFICIENCY 2.2F 80 100 V SW 70 IN 60 LTC3539 V = 2.4V V IN OUT 50 10 PWM BURST MODE V OUT V = 3.3V 3.3V OUT 600mA 40 1M 33pF POWER LOSS 30 OFF ON SHDN FB 22F 1 2 20 GND PGND 562k FREQUENCY = 1MHz 10 FREQUENCY = 2MHz 3539 TA01a 0 0.1 0.1 1 10 100 1000 I AVERAGE (mA) 3539 TA01b LOAD 35392fc 1 For more information www.linear.com/3539/3539-2 EFFICIENCY (%)LTC3539/LTC3539-2 ABSOLUTE MAXIMUM RATINGS PIN CONFIGURATION (Note 1) TOP VIEW V Voltage ................................................... 0.3V to 6V IN SW 1 8 V OUT SW Voltage PGND 2 7 MODE DC ............................................................ 0.3V to 6V 9 GND 3 6 FB Pulsed <100ns ......................................... 0.3V to 7V V 4 5 SHDN IN SHDN, FB, MODE Voltage ............................ 0.3V to 6V DCB PACKAGE V ............................................................. 0.3V to 6V OUT 8-LEAD (2mm 3mm) PLASTIC DFN Operating Temperature (Notes 2, 5) .........40C to 85C T = 125C, = 64C/W (NOTE 6) JMAX JA EXPOSED PAD (PIN 9) IS GND, MUST BE SOLDERED TO PCB Storage Temperature Range .................. 65C to 125C ORDER INFORMATION LEAD FREE FINISH TAPE AND REEL PART MARKING PACKAGE DESCRIPTION TEMPERATURE RANGE LTC3539EDCB PBF LTC3539EDCB TRPBF LDCS 8-Lead (2mm 3mm) Plastic DFN 40C to 85C LTC3539EDCB-2 PBF LTC3539EDCB-2 TRPBF LDPH 8-Lead (2mm 3mm) Plastic DFN 40C to 85C Consult LTC Marketing for parts specified with wider operating temperature ranges. Consult LTC Marketing for information on non-standard lead based finish parts. For more information on lead free part marking, go to: