LT1301

Features:

 12V at 120mA from 5V or 3.3V Supply
Supply Voltage as Low as 1.8V
Better High Current Efficiency Than CMOS
Up to 89% Efficiency
120A Quiescent Current
Shutdown to 10A
Programmable 5V or 12V Output
Low V_CESAT Switch: 170mV at 1A Typical
I_LIM Pin Programs Peak Switch Current
Uses Inexpensive Surface Mount Inductors
8-Lead DIP or SOIC Package


Application

 Flash Memory V_PP Generator
  Palmtop Computers
  Portable Instruments
  Bar-Code Scanners
  Personal Digital Assistants
  PCMCIA Cards


Pinout




Specifications

V_IN Voltage .............................................................. 10V
SW1 Voltage ............................................................ 20V
Sense Voltage .......................................................... 20V
Shutdown Voltage ................................................... 10V
Select Voltage .......................................................... 10V
I_LIM Voltage ............................................................ 0.5V
Maximum Power Dissipation ................................500mW
Operating Temperature Range
   LT1301C .................................................0°C to 70°C
   LT1301I ................................................40°C to 85°C
Storage Temperature Range ..............65°C to 150°C
Lead Temperature (Soldering, 10 sec)..................300°C


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 120A and a shutdown pin which reduces supply current to 10A. The on-chip power switch has a low 170mV saturation voltage at a switch current of 1A, a four-fold reduction over prior designs. A 155kHz 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 I_LIM 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.