LT1301 Datasheet | Linear Technology

LT1301 Micropower High Efficiency 5V/12V Step-Up DC/DC Converter for Flash Memory Features s s s s s s s s s s s DESCRIPTION The LT1301 is a micropower step-up DC/DC converter that utilizes Burst Mode™ operation. The device can deliver 5V or 12V from a two-cell battery input. It Features programmable 5V or 12V output via a logic-controlled input, noload quiescent current of 120µA and a shutdown pin which reduces supply current to 10µA. The on-chip power switch has a low 170m V saturation voltage at a switch current of 1A, a four-fold reduction over prior designs. A 155k Hz internal oscillator allows the use of extremely small surface mount inductors and capacitors. Operation is guaranteed at 1.8V input. This allows more energy to be extracted from the battery, increasing operating life. The ILIM pin can be used for soft start or to program peak switch current with a single resistor allowing the use of even smaller inductors in lighter load applications. The LT1301 is available in an 8-lead SOIC package, minimizing board space requirements. For a selectable 3.3V/5V step-up converter, please see the LT1300. For higher output power, see the LT1302. Burst Mode is a trademark of Linear Technology Corporation. U APPLICATIONS s s s s s s 12V at 120m A from 5V or 3.3V Supply Supply Voltage as Low as 1.8V Better High Current Efficiency Than CMOS Up to 89% Efficiency 120µA Quiescent Current Shutdown to 10µA Programmable 5V or 12V Output Low VCESAT Switch: 170m V at 1A Typical ILIM Pin Programs Peak Switch Current Uses Inexpensive Surface Mount Inductors 8-Lead DIP or SOIC Package Flash Memory VPP Generator Palmtop puters Portable Instruments Bar-Code Scanners Personal Digital Assistants PCMCIA Cards TYPICAL APPLICATIONS N 5V OR 3.3V VIN SELECT L1 33µH D1 Output Voltage 12V OUTPUT 12V VOUT 2V/DIV SW SENSE 47µF SHUTDOWN SHDN PGND + C2 ILIM GND N/C 33µF 20V 0.1µF- SHUTDOWN 10V/DIV 1ms/DIV LT1301 F1 EFFICIENCY (%) + C1 - REQUIRED FOR 5V OUTPUT L1 = COILCRAFT...