Compact 3-A Buck Converter Powers Smart Meters, Consumer Appliances

The new buck converter from STMicroelectronics, which helps simplify power design, features 93% efficiency and a low BOM.
April 28, 2026

Unveiled at APEC 2026, STMicroelectronics’ DCP3603 monolithic 3-A buck converter simplifies design, saves PCB space, and accelerates time-to-market while enhancing system reliability. With a 3.3- to 36-V input-voltage range, this convenient miniature converter can power equipment such as smart meters, domestic appliances, and industrial 24-V loads.

Available with either a 1-MHz or 500-kHz fixed switching frequency, the DCP3603 can be configured for forced-PWM (pulse-width modulation) operation for optimal performance in noise-sensitive applications, or pulse-skipping. Both variants use synchronous rectification and implement frequency dithering to reduce switching noise emissions and maintain high efficiency across their load range.

Measuring a mere 3 × 1.6 mm, the converter integrates a set of power switches and compensation elements. It requires only an inductor, bootstrap and filter capacitors, and feedback resistors to implement a complete solution.

The DCP3603 is in production now, in a SOT23 6-lead package, priced from $0.44 for orders of 1,000 pieces. A dedicated evaluation board, the STEVAL-3603BC1, is also available.

>>Check out more of our APEC 2026 coverage

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About the Author

Lee Goldberg

Contributing Editor

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.

Lee also writes the regular PowerBites series