LT1109A Micropower DC/DC Converter Flash Memory VPP Generator Adjustable and Fixed 5V, 12V DESCRIPTIO FEATURES n Uses Off-the-Shelf Inductors The LT1109A is a simple step-up DC/DC converter. The 8- n Low Cost pin DIP or SOIC devices require only four external compo- n 8-Pin DIP or SO Package nents to construct a complete DC/DC converter. Current n Fixed 5V or 12V Output or Adjustable Version drain is just 360m A at no load, making the device ideal for n Only Four External Components Required cost-sensitive applications where standby current must n 360m A Standby Current be kept to a minimum. n Logic-Controlled Shutdown The LT1109A-12 can deliver 12V at over 150mA from a 5V supply, enough power to program four flash memory APPLICATI S chips simultaneously. The LT1109A-5 can deliver 5V at up to 110mA from a 2V input. The devices feature a shutdown n Flash Memory VPP Generators pin that turns off the oscillator when taken low. The gated- n 5V to 12V Converters oscillator design requires no frequency compensation n 3.3V to 12V Converters components. High frequency 120kHz operation permits n Disk Drives the use of small surface mount inductors and capacitors. n PC Plug-In Cards n Peripherals n Battery-Powered Equipment TYPICAL APPLICATI All Surface Mount Output Voltage Flash Memory VPP Generator Output Current 13.0 L1* MBRS130T3 12V 33m H 12.5 3 V OUT SW V = 5V 2V/DIV IN 1 8 +V V IN OUT 12.0 V SENSE IN 5V 12V LT1109ACS8-12 C1 + + C2 SHUTDOWN 11.5 22m F 7 47m F V = 4.5V IN 5V/DIV SHUTDOWN 10V 20V PGND GND 500m s/DIV 11.0 1109A TA03 45 ** 10.5 * COILTRONICS CTX33-2 SUMIDA CD54-330LC 10.0 ** 1 = PROGRAM 0 50 100 150 200 250 300 0 = SHUTDOWN 1109A TA01 OUTPUT CURRENT (mA) 1109A TA02 1 OUTPUT VOLTAGE (V) UO UO ULT1109A ABSOLUTEXAI U RATI GS (Voltages Referred to GND Pin) Switch Current .......................................................... 2A Supply Voltage (V ) ................................ 0.4V to 20V Maximum Power Dissipation ............................ 300mW IN SW Pin Voltage ........................................ 0.4V to 50V Operating Temperature Range .................... 0 C to 70 C Feedback Pin Voltage (LT1109A) ........................... 5.5V Storage Temperature Range ................ 65 C to 150 C Shutdown Pin Voltage ........................................... 5.5V Lead Temperature (Soldering, 10 sec).................. 300 C PACKAGE/ORDER I FOR ATIO TOP VIEW TOP VIEW ORDER PART ORDER PART S8 PART NUMBER NUMBER MARKING V 1 FB (SENSE)* V FB (SENSE)* 8 1 8 IN IN NC 2 7 SHUTDOWN NC 2 7 SHUTDOWN 1109A LT1109ACN8 LT1109ACS8 SW 3 NC SW NC 6 3 6 1109A5 LT1109ACN8-5 LT1109ACS8-5 PGND 4 5 GND PGND GND 4 5 1109A1 LT1109ACN8-12 LT1109ACS8-12 N8 PACKAGE S8 PACKAGE 8-LEAD PLASTIC DIP 8-LEAD PLASTIC SO *FIXED VERSIONS *FIXED VERSIONS T = 90 C, q = 130 C/W T = 90 C, q = 150 C/W JMAX JA JMAX JA ELECTRICAL CHARACTERISTICS T = 25 C, V = 3V, unless otherwise noted. A IN SYMBOL PARAMETER CONDITIONS MIN TYP MAX UNITS I Quiescent Current Switch Off l 360 500 m A Q V Input Voltage l 29 V IN Comparator Trip Point Voltage LT1109A l 1.20 1.25 1.30 V V Output Sense Voltage LT1109A-5 2V V 5V l 4.75 5.00 5.25 V OUT IN LT1109A-12 2V V 12V l 11.52 12.00 12.55 V IN Comparator Hysteresis LT1109A l 8 12.5 mV Output Voltage Ripple LT1109A-5 l 25 50 mV LT1109A-12 l 60 120 mV f Oscillator Frequency 105 120 135 kHz OSC l 95 155 kHz t Switch On Time 4.1 5.5 6.9 m s ON l 3.8 7.4 m s DC Duty Cycle Full Load l 60 68 77 % V Switch Saturation Voltage V = 3V, I = 650mA l 0.5 0.65 V CESAT IN SW V = 5V, I = 1A 0.7 1.00 V IN SW Switch Leakage Current V = 12V 1 10 m A SW V SHUTDOWN Pin High l 2.0 V IH V SHUTDOWN Pin Low l 0.8 V IL I SHUTDOWN Pin Input Current V 2.0V l 10 m A IH SHUTDOWN I SHUTDOWN Pin Input Current 0V V 0.8V l 20 m A L SHUTDOWN The l denotes specifications which apply over the full operating temperature range. 2 U WU U W W W