The Story behind the LTC3124

Background

Modern industrial and commercial applications continue to require increasingly complex electronic systems. The power requirements for these systems continue to grow while the available space for power conversion solutions continually shrinks. Furthermore, electrical performance criteria of these power ICs becomes more demanding. For example, many RF Transceiver amplifiers require a well regulated 12V output voltage with a load in excess of 1A, regardless if the power source is a Li-Ion battery, multiple cells of alkaline batteries or a fixed 5V rail. Similarly, high efficiency is of paramount importance as it minimizes thermal design considerations while also maximizing battery run time. High switching frequencies are also required to keep switching noise out of noise sensitive frequency bands and to keep externals components as small as possible, minimizing the solution footprint.  Additionally, in many applications, low quiescent current is required to maximize battery run time since this minimizes the power drawn from the battery when the IC is in standby mode.

The New Direction

Linear Technology continues to grow its family of monolithic synchronous boost converters to specifically address these requirements. The LTC3124 offers the first dual-phase 15V, 5A monolithic synchronous boost DC/DC converter. It can operate from a wide 1.8V to 5.5V input voltage range which can accommodate a wide range battery inputs as well as fixed rails. The 2.5V to 15V output voltage range is ideal for a wide array of commercial and industrial applications. Dual-phase switching reduces both input and output ripple which is critical is many low noise applications. The device provides improved performance in all key areas including size, efficiency, and ease of design, as well as excellent thermal performance.

LTC3124 Key Features

•VIN Range: 1.8V to 5.5V, 500mV After Start-Up

•Adjustable Output Voltage: 2.5V to 15V

•1.5A Output Current for VIN = 5V and VOUT = 12V

•Dual-Phase Control Reduces Output Voltage Ripple

•Output Disconnects from Input When Shut Down

•Synchronous Rectification: Up to 95% Efficiency

•Inrush Current Limit

•Up to 3MHz Programmable Switching Frequency Synchronizable to External Clock

•Selectable Burst ModeR Operation: 25μA IQ

•Output Overvoltage Protection

•Internal Soft-Start

•<1μA IQ in Shutdown

•16-Lead, Thermally- Enhanced 3mm × 5mm × 0.75mm DFN & TSSOP Packages