Microwave Journal

Linear Technology Announces Fixed Frequency Synchronous Buck Converters

November 29, 2011

Linear Technology announces the LTC3103 and the LTC3104, 15 V, fixed frequency synchronous buck converters capable of delivering 300 mA of continuous current to output voltages from 0.6 to 13.8 V. The LTC3103 consumes just 1.8 µA of quiescent current, while the LTC3104 (which offers a 10 mA programmable LDO output) requires only 2.6 µA of quiescent current. These devices are ideal for a wide range of battery-powered applications including industrial control power, remote sensor networks, low power wireless systems and energy harvesting applications. Both devices operate from an input voltage range of 2.5 to 15 V facilitating operation from a wide range of input sources, including single- or multi-cell batteries, supercapacitors and system rails.

The LTC3103 and LTC3104 operate at a fixed 1.2 MHz switching frequency and utilize synchronous rectification to deliver efficiencies as high as 95 percent. For applications that demand low noise, both the LTC3103 and LTC3104 can operate in a “forced continuous mode” where the part will operate at the 1.2 MHz switching frequency. The device can also be commanded to automatically transition from fixed frequency to Burst Mode® operation to achieve high efficiency over an extremely wide range of load currents. Internal compensation, small-footprint DFN and MSOP packages and fixed 1.2 MHz switching frequency enable the use of just a few tiny external components to offer very compact solution footprints. An accurate, programmable RUN comparator offers the user flexibility in programming at what input voltage the part will be enabled. Other features include Power Good, integrated soft-start, and over-temperature protection.