LT1933 600mA, 500kHz Step-Down Switching Regulator in SOT-23 and DFN Packages FEATURES DESCRIPTION n Wide Input Range: 3.6V to 36V The LT 1933 is a current mode PWM step-down DC/DC n 5V at 600mA from 16V to 36V Input converter with an internal 0.75A power switch, packaged n 3.3V at 600mA from 12V to 36V Input in a tiny 6-lead SOT-23. The wide input range of 3.6V n 5V at 500mA from 6.3V to 36V Input to 36V makes the LT1933 suitable for regulating power n 3.3V at 500mA from 4.5V to 36V Input from a wide variety of sources, including unregulated wall n Fixed Frequency 500kHz Operation transformers, 24V industrial supplies and automotive n Uses Tiny Capacitors and Inductors batteries. Its high operating frequency allows the use of n Soft-Start tiny, low cost inductors and ceramic capacitors, resulting n Internally Compensated in low, predictable output ripple. n Low Shutdown Current: <2A Cycle-by-cycle current limit provides protection against n Output Adjustable Down to 1.25V shorted outputs, and soft-start eliminates input current n Low Pro le (1mm) SOT-23 (ThinSOT) and surge during start up. The low current (<2A) shutdown (2mm 3mm 0.75mm) 6-Pin DFN Packages provides output disconnect, enabling easy power manage- ment in battery-powered systems. APPLICATIONS L, LT, LTC, LTM, Linear Technology and the Linear logo are registered trademarks of Linear Technology Corporation. ThinSOT is a trademark of Linear Technology Corporation. All other n trademarks are the property of their respective owners. Automotive Battery Regulation n Industrial Control Supplies n Wall Transformer Regulation n Distributed Supply Regulation n Battery-Powered Equipment TYPICAL APPLICATION Ef ciency 95 V = 12V 3.3V Step-Down Converter IN 90 1N4148 V = 5V OUT V IN V BOOST IN 4.5V TO 36V 85 LT1933 0.1F 22H V = 3.3V OUT V OUT OFF ON SHDN SW 80 3.3V/500mA GND FB MBRM140 75 16.5k 2.2F 22F 10k 70 65 1933 TA01a 0 100 200 300 400 500 600 LOAD CURRENT (mA) 1933 TA01b 1933fe 1 EFFICIENCY (%)LT1933 ABSOLUTE MAXIMUM RATINGS (Note 1) LT1933I .................................................. 40C to 125C Input Voltage (V ) ..................................... 0.4V to 36V IN LT1933H ................................................ 40C to 150C BOOST Pin Voltage ...................................................43V Maximum Junction Temperature BOOST Pin Above SW Pin .........................................20V LT1933E, LT1933I ................................................. 125C SHDN Pin ................................................... 0.4V to 36V LT1933H ............................................................... 150C FB Voltage .................................................... 0.4V to 6V Storage Temperature Range .................. 65C to 150C Operating Temperature Range (Note 2) Lead Temperature, S6 Package LT1933E ...................................................40C to 85C (Soldering, 10 sec) ............................................300C PIN CONFIGURATION TOP VIEW TOP VIEW BOOST 1 6 FB BOOST 1 6 SW 7 V 2 5 GND IN GND 2 5 V IN SW 3 4 SHDN FB 3 4SHDN S6 PACKAGE DCB PACKAGE 6-LEAD PLASTIC TSOT-23 6-LEAD (2mm 3mm) PLASTIC DFN = 165C/W, = 102C/W JA JC = 73.5C/W, = 12C/W JA JC EXPOSED PAD (PIN 7) IS GND, MUST BE SOLDERED TO PCB ORDER INFORMATION LEAD FREE FINISH TAPE AND REEL PART MARKING PACKAGE DESCRIPTION TEMPERATURE RANGE LT1933IDCB PBF LT1933IDCB TRPBF LCGM 40C to 125C 6-Lead (2mm 3mm) Plastic DFN LT1933HDCB PBF LT1933HDCB TRPBF LCGN 40C to 150C 6-Lead (2mm 3mm) Plastic DFN LT1933ES6 PBF LT1933ES6 TRPBF LTAGN 6-Lead Plastic TSOT-23 40C to 85C LT1933IS6 PBF LT1933IS6 TRPBF LTAGP 6-Lead Plastic TSOT-23 40C to 125C LT1933HS6 PBF LT1933HS6 TRPBF LTDDQ 6-Lead Plastic TSOT-23 40C to 150C LEAD BASED FINISH TAPE AND REEL PART MARKING PACKAGE DESCRIPTION TEMPERATURE RANGE LT1933IDCB LT1933IDCB TR LCGM 40C to 125C 6-Lead (2mm 3mm) Plastic DFN LT1933HDCB LT1933HDCB TR LCGN 6-Lead (2mm 3mm) Plastic DFN 40C to 150C LT1933ES6 LT1933ES6 TR LTAGN 6-Lead Plastic TSOT-23 40C to 85C LT1933IS6 LT1933IS6 TR LTAGP 6-Lead Plastic TSOT-23 40C to 125C LT1933HS6 LT1933HS6 TR LTDDQ 6-Lead Plastic TSOT-23 40C to 150C Consult LTC Marketing for parts speci ed with wider operating temperature ranges. For more information on lead free part marking, go to: