GaN DC-DC Converter Lifts Efficiency and Power-Density Levels
The LMG708B0, a gallium-nitride (GaN) synchronous buck DC-DC converter, provides very high current density and power-conversion efficiency for applications such as automotive audio and headlights. The integrated GaN power stage reduces design complexity by combining the controller, drivers, GaN FETs, and bootstrap circuit into a single package, offering an alternative to existing bulky controller-plus-discrete MOSFET solutions.
Developed by Texas Instruments, the device’s co-packaged low RDS(on) GaN FETs have near-zero deadtime switching and can deliver up to 20 A of output current across a wide input voltage range of 5 to 80 V. The converter is phase-stackable and supports synchronized interleaving. Its peak current-mode architecture supports accurate current sharing for even higher output current.
In addition, the architecture’s shared compensation allows it to seamlessly transition between its constant-voltage (CV) mode and constant-current (CC) operation regulation for battery charging and other current-source type loads. It also achieves ±1% voltage accuracy and ±4.5% current regulation.
The LMG708B0’s VSET and ISET inputs facilitate dynamic adjustment of the respective CV and CC loop setpoints, and an IMON output provides average output current monitoring. It comes in a thermally enhanced package (TEP) with optional top-side cooling (TSC) through exposed package connections and low package parasitic inductance for quiet switching performance.
The following provides additional information about the LMG708B0:
About the Author
Lee Goldberg
Contributing Editor
Lee is the author of the popular PowerBites series.
Lee Goldberg is a self-identified “Recovering Engineer,” Maker/Hacker, Green-Tech Maven, Aviator, Gadfly, and Geek Dad. He spent the first 18 years of his career helping design microprocessors, embedded systems, renewable energy applications, and the occasional interplanetary spacecraft. After trading his ‘scope and soldering iron for a keyboard and a second career as a tech journalist, he’s spent the next two decades at several print and online engineering publications.
Lee’s current focus is power electronics, especially the technologies involved with energy efficiency, energy management, and renewable energy. This dovetails with his coverage of sustainable technologies and various environmental and social issues within the engineering community that he began in 1996. Lee also covers 3D printers, open-source hardware, and other Maker/Hacker technologies.
Lee holds a BSEE in Electrical Engineering from Thomas Edison College, and participated in a colloquium on technology, society, and the environment at Goddard College’s Institute for Social Ecology. His book, “Green Electronics/Green Bottom Line - A Commonsense Guide To Environmentally Responsible Engineering and Management,” was published by Newnes Press.
Lee, his wife Catherine, and his daughter Anwyn currently reside in the outskirts of Princeton N.J., where they masquerade as a typical suburban family.