Ideal-Diode Controllers Simplify Reverse Battery Polarity, Overvoltage Protection
According to Diodes Inc., its AP74502Q and AP74502HQ automotive-compliant, 80-V ideal-diode controllers provide robust, reliable protection against reverse connections and voltage transients.
These devices are primarily intended for use in the growing number of EVs and PHEVs that use a 48-V primary supply to power features like electric turbocharging, improved regenerative braking, and electrified auxiliary components. Typical applications include advanced driver-assistance systems (ADAS), body control modules, infotainment systems, exterior lighting, and USB charging ports.
The ideal-diode controllers have all of the features necessary to implement an efficient and fast reverse-polarity protection circuit. They also include a load disconnect function in case of overvoltage and undervoltage events. Unlike conventional ideal diodes with reverse-current blocking features, these devices are suitable for applications where energy may return to the input supply. However, they can be configured as surge stoppers as well.
The AP74502Q and AP74502HQ controllers also support input voltages as low as 3.2 V, ensuring correct and reliable operation even during severe cold-crank conditions. Both devices share a peak gate turn-off sink current of 2.3 A, enabling rapid turn-off of the external N-channel MOSFETs when required, for example, during overvoltage or undervoltage events.
The controllers are available in the industry-standard SOT28 package with an operating temperature range from −40 to +125°C. Both devices are available at $0.27 each in 1,000-piece quantities.
Next in This Edition of PowerBites
More PowerBites
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.