LT1617/LT1617-1 Micropower Inverting DC/DC Converters in SOT-23 FEATURES DESCRIPTIO n Low Quiescent Current: The LT 1617/LT1617-1 are micropower inverting DC/DC 20m A in Active Mode converters in a 5-lead SOT-23 package. The LT1617 is <1m A in Shutdown Mode designed for higher power systems with a 350mA current n Operates with V as Low as 1V limit and an input voltage range of 1.2V to 15V, whereas IN n Low V Switch: 250mV at 300mA the LT1617-1 is intended for lower power and single-cell CESAT n Uses Small Surface Mount Components applications with a 100mA current limit and an extended n High Output Voltage: Up to 34V input voltage range of 1V to 15V. Otherwise, the two n Tiny 5-Lead SOT-23 Package devices are functionally equivalent. Both devices feature a quiescent current of only 20m A at no load, which further U reduces to 0.5m A in shutdown. A current limited, fixed off- APPLICATIO S time control scheme conserves operating current, result- ing in high efficiency over a broad range of load current. n LCD Bias The 36V switch allows high voltage outputs up to 34V to n Handheld Computers be easily generated without the use of costly transformers. n Battery Backup The LT1617s low off-time of 400ns permits the use of n Digital Cameras tiny, low profile inductors and capacitors to minimize footprint and cost in space-conscious portable applications. , LTC and LT are registered trademarks of Linear Technology Corporation. TYPICAL APPLICATION 1-Cell Li-Ion to 15V Inverting Converter Efficiency C3 80 L1 L2 0.22F 22H 22H V 15V IN V = 4.2V 75 IN 2.5V TO 4.2V 12mA 5 1 V SW 70 IN D1 267k V = 2.5V IN C2 LT1617 65 4.7F 43 SHDN NFB GND C1 60 24.9k 4.7F 2 55 C1: TAIYO YUDEN LMK316BJ475 1617/-1 TA01 C2: TAIYO YUDEN EMK316BJ475 50 C3: TAIYO YUDEN TMK316BJ224 0.1 1 10 30 L1, L2: MURATA LQH3C220K34 LOAD CURRENT (mA) D1: MOTOROLA MBR0530 1617/-1 TA01a 1 EFFICIENCY (%) U ULT1617/LT1617-1 UUW ABSOLUTE AXI U RATI GS PACKAGE/ORDER I FOR ATIO (Note 1) ORDER PART TOP VIEW V , SHDN Voltage ................................................... 15V NUMBER IN SW Voltage .............................................................. 36V SW 1 5 V IN LT1617ES5 GND 2 NFB Voltage ............................................................. 3V LT1617ES5-1 NFB 3 4 SHDN Current into NFB Pin ............................................. 1mA Junction Temperature........................................... 125 C S5 PACKAGE S5 PART MARKING 5-LEAD PLASTIC SOT-23 Operating Temperature Range (Note 2) .. 40 C to 85 C T = 125 C, q = 256 C/W JMAX JA LTKF Storage Temperature Range ................. 65 C to 150 C LTKA 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. V = 1.2V, V = 1.2V unless otherwise noted. A IN SHDN PARAMETER CONDITIONS MIN TYP MAX UNITS Minimum Input Voltage LT1617-1 1.0 V LT1617 1.2 V Quiescent Current Not Switching 20 30 m A V = 0V 1 m A SHDN FB Comparator Trip Point l 1.205 1.23 1.255 V FB Comparator Hysteresis 8mV Output Voltage Line Regulation 1.2V < V < 12V 0.05 0.1 %/V IN FB Pin Bias Current (Note 3) V = 1.23V l 1.3 2 2.7 m A NFB Switch Off Time 400 ns Switch V I = 60mA (LT1617-1) 85 120 mV CESAT SW I = 300mA (LT1617) 250 350 mV SW Switch Current Limit LT1617-1 75 100 125 mA LT1617 300 350 400 mA SHDN Pin Current V = 1.2V 2 3 m A SHDN V = 5V 8 12 m A SHDN SHDN Input Voltage High 0.9 V SHDN Input Voltage Low 0.25 V Switch Leakage Current Switch Off, V = 5V 0.01 5 m A SW Note 1: Absolute Maximum Ratings are those values beyond which the life of a device may be impaired. Note 2: The LT1617 and LT1617-1 are guaranteed to meet specifications 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: Bias current flows out of the NFB pin. 2 U WWW