LT1073

U U FEATURES s No Design Required s Operates at Supply Voltages from 1V to 30V s Consumes Only 95µA Supply Current s Works in Step-Up or Step-Down Mode s Only Three External Off-the-Shelf Components Required s Low-Battery Detector Comparator On-Chip s User-Adjustable Current Limit s Internal 1A Power Switch s Fixed or Adjustable Output Voltage Versions s Space-Saving 8-Pin PDIP or SO-8 Package U APPLICATIO S s Pagers s Cameras s Single-Cell to 5V Converters s Battery Backup Supplies s Laptop and Palmtop Computers s Cellular Telephones s Portable Instruments s 4mA to 20mA Loop Powered Instruments s Hand-Held Inventory Computers s Battery-Powered α, β, and γ Particle Detectors LT1073 Micropower DC/DC Converter Adjustable and Fixed 5V, 12V DESCRIPTIO The LT®1073 is a versatile micropower DC/DC converter. The device requires only three external components to deliver a fixed output of 5V or 12V. The very low minimum supply voltage of 1V allows the use of the LT1073 in applications where the primary power source is a single cell. An on-chip auxiliary gain block can function as a lowbattery detector or linear post-regulator. Average current drain of the LT1073-5 used as shown in the Typical Application circuit below is just 135µA unloaded, making it ideal for applications where long battery life is important. The circuit shown can deliver 5V at 40mA from an input as low as 1.25V and 5V at 10mA from a 1V input. The device can easily be configured as a step-up or stepdown converter,...