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
• 120µA Quiescent Current
• Shutdown to 10µA
• 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

Typical Application

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, no-load quiescent current of 120µA and a shutdown pin which reduces supply current to 10µA. 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.