LT3503 1A, 2.2MHz Step-Down Switching Regulator in 2mm 3mm DFN FEATURES DESCRIPTIO Wide Input Range: 3.6V to 20V The LT 3503 is a current mode PWM step-down DC/DC 5V at 1.2A from 11V to 18V Input converter with an internal 1.45A power switch. The wide 5V at 1A from 7.2V to 18V Input operating input range of 3.6V to 20V makes the LT3503 3.3V at 1.2A from 8.5V to 12V Input ideal for regulating power from a wide variety of sources. 3.3V at 1A from 5.5V to 12V Input Its high operating frequency allows the use of tiny, low Fixed Frequency Operation: 2.2MHz cost inductors and ceramic capacitors, resulting in low, Output Adjustable Down to 780mV predictable output ripple. Short-Circuit Robust Cycle-by-cycle current limit provides protection against Uses Tiny Capacitors and Inductors shorted outputs and soft-start eliminates input current Soft-Start surge during start-up. The low current (<2A) shutdown Internally Compensated mode provides output disconnect, enabling easy power Low Shutdown Current: <2A management in battery-powered systems. Low V Switch: 400mV at 1A CESAT , LT, LTC and LTM are registered trademarks of Linear Technology Corporation. Thermally Enhanced, 2mm 3mm 6-Pin DFN All other trademarks are the property of their respective owners. Low Profile Package U APPLICATIO S Automotive Battery Regulation Industrial Control Supplies Wall Transformer Regulation Distributed Supply Regulation Battery-Powered Equipment TYPICAL APPLICATIO Efficiency 3.3V Step-Down Converter 85 V = 12V IN V OUT V IN 80 3.3V 4.5V TO 12V V BOOST IN 1A, V > 5.5V IN 20V MAX 0.1F LT3503 1.2A, V > 8.5V IN 75 2.5H SW ON OFF SHDN 70 37.4k 120pF GND FB 10F 65 11.5k 1F 60 3503 TA01a 55 50 0 0.2 0.4 0.6 0.8 1.0 1.2 LOAD CURRENT (A) 3503 TA01b 3503f 1 EFFICIENCY (%) U ULT3503 UUW ABSOLUTE AXI U RATI GS PACKAGE/ORDER I FOR ATIO (Note 1) TOP VIEW Input Voltage (V ) .................................................. 20V IN BOOST Pin Voltage .................................................. 40V FB 1 6 SHDN BOOST Pin Above SW Pin ....................................... 20V GND 7 5 V 2 IN SHDN Pin ................................................................ 20V BOOST 4 SW 3 FB Voltage ................................................................. 6V Operating Temperature Range (Note 2) ... 40C to 85C DCB PACKAGE 6-LEAD (2mm 3mm) PLASTIC DFN Maximum Junction Temperature .......................... 125C T = 125C, = 64C/ W JMAX JA Storage Temperature Range ................. 65C to 150C EXPOSED PAD (PIN 7) IS GND, MUST BE SOLDERED TO PCB ORDER PART NUMBER DCB PART MARKING LT3503EDCB LCGW Order Options Tape and Reel: Add TR Lead Free: Add PBF Lead Free Tape and Reel: Add TRPBF Lead Free Part Marking: