LT1613 1.4MHz, Single Cell DC/DC Converter in 5-Lead SOT-23 FEATURES DESCRIPTIO n Uses Tiny Capacitors and Inductor The LT 1613 is the industrys first 5-lead SOT-23 current n Internally Compensated mode DC/DC converter. Intended for small, low power n Fixed Frequency 1.4MHz Operation applications, it operates from an input voltage as low as n Operates with V as Low as 1.1V 1.1V and switches at 1.4MHz, allowing the use of tiny, low IN n 3V at 30mA from a Single Cell cost capacitors and inductors 2mm or less in height. Its n 5V at 200mA from 3.3V Input small size and high switching frequency enables the n 15V at 60mA from Four Alkaline Cells complete DC/DC converter function to take up less than n High Output Voltage: Up to 34V 0.2 square inches of PC board area. Multiple output power n Low Shutdown Current: <1m A supplies can now use a separate regulator for each output n Low V Switch: 300mV at 300mA voltage, replacing cumbersome quasi-regulated ap- CESAT n Tiny 5-Lead SOT-23 Package proaches using a single regulator and a custom trans- former. U A constant frequency, internally compensated current APPLICATIO S mode PWM architecture results in low, predictable output n Digital Cameras noise that is easy to filter. The high voltage switch on the n Pagers LT1613 is rated at 36V, making the device ideal for boost n Cordless Phones converters up to 34V as well as for Single-Ended Primary n Battery Backup Inductance Converter (SEPIC) and flyback designs. The n LCD Bias device can generate 5V at up to 200mA from a 3.3V supply n Medical Diagnostic Equipment or 5V at 175mA from four alkaline cells in a SEPIC design. n Local 5V or 12V Supply The LT1613 is available in the 5-lead SOT-23 package. n External Modems , LTC and LT are registered trademarks of Linear Technology Corporation. n PC Cards TYPICAL APPLICATIO L1 Efficiency Curve D1 4.7m H 100 V V IN OUT 3.3V 5V 95 200mA R1 V SW IN 90 V = 4.2V 37.4k IN + + C1 C2 85 LT1613 15m F 22m F 80 V = 3.5V IN SHDN SHDN FB 75 GND V = 2.8V R2 IN 70 12.1k 65 V = 1.5V IN L1: MURATA LQH3C4R7M24 OR SUMIDA CD43-4R7 60 C1: AVX TAJA156M010 1613 TA01 C2: AVX TAJB226M006 55 D1: MBR0520 50 0 50 100 150 200 250 300 350 400 Figure 1. 3.3V to 5V 200mA DC/DC Converter LOAD CURRENT (mA) 1613 TA01a 1 EFFICIENCY (%) U ULT1613 ABSOLUTE MAXIMUM RATINGS PACKAGE/ORDER INFORMATION (Note 1) ORDER PART NUMBER V Voltage .............................................................. 10V IN SW Voltage ................................................0.4V to 36V LT1613CS5 TOP VIEW FB Voltage ..................................................... V + 0.3V IN SW 1 5 V Current into FB Pin ............................................... 1mA IN GND 2 SHDN Voltage .......................................................... 10V FB 3 4 SHDN Maximum Junction Temperature .......................... 125 C S5 PART MARKING S5 PACKAGE Operating Temperature Range 5-LEAD PLASTIC SOT-23 LTED Commercial ............................................. 0 C to 70 C Extended Commercial (Note 2)........... 40 C to 85 C Storage Temperature Range ................. 65 C to 150 C Lead Temperature (Soldering, 10 sec).................. 300 C Consult factory for Industrial and Military grade parts. ELECTRICAL CHARACTERISTICS The l denotes the specifications which apply over the full operating temperature range, otherwise specifications are at T = 25 C. Commercial grade 0 C to 70 C, V = 1.5V, V = V unless A IN SHDN IN otherwise noted. (Note 2) PARAMETER CONDITIONS MIN TYP MAX UNITS Minimum Operating Voltage 0.9 1.1 V Maximum Operating Voltage 10 V Feedback Voltage l 1.205 1.23 1.255 V FB Pin Bias Current l 27 80 nA Quiescent Current V = 1.5V 3 4.5 mA SHDN Quiescent Current in Shutdown V = 0V, V = 2V 0.01 0.5 m A SHDN IN V = 0V, V = 5V 0.01 1.0 m A SHDN IN Reference Line Regulation 1.5V V 10V 0.02 0.2 %/V IN Switching Frequency l 1.0 1.4 1.8 MHz Maximum Duty Cycle l 82 86 % Switch Current Limit (Note 3) 550 800 mA Switch V I = 300mA 300 350 mV CESAT SW Switch Leakage Current V = 5V 0.01 1 m A SW SHDN Input Voltage High 1V SHDN Input Voltage Low 0.3 V SHDN Pin Bias Current V = 3V 25 50 m A SHDN V = 0V 0.01 0.1 m A SHDN Note 1: Absolute Maximum Ratings are those values beyond which the life Note 2: The LT1613C is guaranteed to meet performance specifications of a device may be impaired. from 0 C to 70 C. Specifications over the 40 C to 85 C operating temperature range are assured by design, characterization and correlation with statistical process controls. Note 3: Current limit guaranteed by design and/or correlation to static test. 2 U W U W U WW