LT1173 Micropower DC/DC Converter Adjustable and Fixed 5V, 12V FEATURES DESCRIPTIO n Operates at Supply Voltages From 2.0V to 30V The LT1173 is a versatile micropower DC-DC converter. n Consumes Only 110A Supply Current The device requires only three external components to n Works in Step-Up or Step-Down Mode deliver a fixed output of 5V or 12V. Supply voltage ranges n Only Three External Components Required from 2.0V to 12V in step-up mode and to 30V in step-down n Low Battery Detector Comparator On-Chip mode. The LT1173 functions equally well in step-up, step- n User-Adjustable Current Limit down or inverting applications. n Internal 1A Power Switch The LT1173 consumes just 110A supply current at n Fixed or Adjustable Output Voltage Versions standby, making it ideal for applications where low quies- n Space Saving 8-Pin MiniDIP or SO8 Package cent current is important. The device can deliver 5V at 80mA from a 3V input in step-up mode or 5V at 200mA APPLICATI S from a 12V input in step-down mode. n Flash Memory Vpp Generators Switch current limit can be programmed with a single n 3V to 5V, 5V to 12V Converters resistor. An auxiliary gain block can be configured as a low n 9V to 5V, 12V to 5V Converters battery detector, linear post regulator, under voltage lock- n LCD Bias Generators out circuit or error amplifier. n Peripherals and Add-On Cards n Battery Backup Supplies For input sources of less than 2V, use the LT1073. n Laptop and Palmtop Computers n Cellular Telephones n Portable Instruments and LTC are registered trademarks and LT is a trademark of Linear Technology Corporation. TYPICAL APPLICATI S Logic Controlled Flash Memory VPP Generator VPP Output L1* 1N5818 100H 12V 5V IN 100mA 47 V OUT 5V/DIV I V LIM IN 1.07M SW1 0V + + SANYO 10 F LT1173 OS-CON 100 F FB PROGRAM GND SW2 5V/DIV 124k 5ms/DIV 1173 TA02 1N4148 PROGRAM LT1173 TA01 *L1 = GOWANDA GA20-103K EFFICIENCY = 81% COILTRONICS CTX100-4 = 1% METAL FILM NO OVERSHOOT 1 O U UO ULT1173 ABSOLUTEXAI U RATI GS PACKAGE/ORDER I FOR ATIO Supply Voltage (V ) ................................................ 36V IN TOP VIEW ORDER PART SW1 Pin Voltage (V ) .......................................... 50V SW1 I 1 8 FB (SENSE)* LIM NUMBER SW2 Pin Voltage (V ) ............................. 0.5V to V SW2 IN V 2 7 SET IN Feedback Pin Voltage (LT1173) ................................. 5V SW1 3 AO LT1173CN8 6 Sense Pin Voltage (LT1173, -5, -12) ....................... 36V SW2 4 5 GND LT1173CN8-5 Maximum Power Dissipation ............................. 500mW LT1173CN8-12 N8 PACKAGE Maximum Switch Current ....................................... 1.5A 8-LEAD PLASTIC DIP *FIXED VERSIONS Operating Temperature Range ..................... 0C to 70C T = 90C, = 130C/W JMAX JA Storage Temperature Range .................. 65C to 150C TOP VIEW Lead Temperature, (Soldering, 10 sec.)................ 300C LT1173CS8 I 1 8 FB (SENSE)* LIM LT1173CS8-5 V 2 7 SET IN Consult factory for Industrial and Military grade parts LT1173CS8-12 SW1 AO 3 6 S8 PART MARKING SW2 GND 4 5 S8 PACKAGE 1173 8-LEAD PLASTIC SOIC 11735 *FIXED VERSIONS 117312 T = 90C, = 150C/W JMAX JA ELECTRICAL CHARACTERISTICS T = 25C, V = 3V, unless otherwise noted. A IN SYMBOL PARAMETER CONDITIONS MIN TYP MAX UNITS I Quiescent Current Switch Off l 110 150 A Q I Quiescent Current, Boost No Load LT1173-5 135 A Q Mode Configuration LT1173-12 250 A V Input Voltage Step-Up Mode l 2.0 12.6 V IN Step-Down Mode l 30 V Comparator Trip Point Voltage LT1173 (Note 1) l 1.20 1.245 1.30 V V Output Sense Voltage LT1173-5 (Note 2) l 4.75 5.00 5.25 V OUT LT1173-12 (Note 2) l 11.4 12.0 12.6 V Comparator Hysteresis LT1173 l 510 mV Output Hysteresis LT1173-5 l 20 40 mV LT1173-12 l 50 100 mV f Oscillator Frequency l 18 23 30 kHz OSC Duty Cycle Full Load l 43 51 59 % t Switch ON Time I tied to V l 17 22 32 s ON LIM IN Feedback Pin Bias Current LT1173, V = 0V l 10 50 nA FB Set Pin Bias Current V = V l 20 100 nA SET REF V Gain Block Output Low I = 100A, V = 1.00V l 0.15 0.4 V OL SINK SET Reference Line Regulation 2.0V V 5V l 0.2 0.4 %/V IN 5V V 30V l 0.02 0.075 %/V IN V SW Voltage, Step-Up Mode V = 3.0V, I = 650mA l 0.5 0.65 V SAT SAT IN SW V = 5.0V, I = 1A 0.8 1.0 V IN SW l 1.4 V 2 U WU U W W W