This 1mm 'fan on a chip' could put active cooling inside ultra-thin gadgets

What if you could take the benefits of solid-state speaker drivers — specifically, their extreme thinness and lack of moving parts — and bring them to cooling fans? That's what xMEMS aims to do with its new XMC-2400 µCooling (microcooling) chip. It's a 1mm-tall solid-state fan on a chip that can actively cool extremely thin devices like smartphones and tablets. Based on the same MEMS (Micro-electromechanical systems) technology as the company's upcoming ultrasonic driver inside headphones, the micro-cooling chip could lead to slim devices that are less prone to overheating and capable of better sustained performance.

Consider this real-world example: If my fan-less M2 MacBook Air had xMEMS' XMC-2400 chips installed, it wouldn't have died on me while I was working in the sun at Apple's WWDC last year. It's not hard to imagine other potential solutions: Headphones that can cool down your ears; gaming controllers that can keep your paws from getting sweaty; tablets that can eke out even more speed from their hardware.

In earbuds like Creative's Aurvana Ace, xMEMS' solid-state drivers excelled at reproducing mid- and high-range, but they were paired together with a traditional bass driver to handle low-end frequencies. xMEMS' next-generation solid-state driver, dubbed Cypress, holds its own across all frequencies—-and it's that same air-pushing power that the new micro-cooling chip relies on.

According to Mike Housholder, xMEMS VP Marketing and Business Development, the XMC-2400 µCooling chip uses ultrasonic modulation to create pressure pulses for air movement. It weighs less than 150 milligrams and can move "up to 39 cubic centimeters of air per second with 1,000 Pascals of back pressure," xMEMS says. Since it's a solid-state device, there aren't any moving parts like rotors or fins to fail, and its thin design means it can be placed directly atop heat-generating components like APUs and GPUs. It's also resistant to dust and water damage with an IP58 rating.

xMEMS isn't the only company pursuing ultra-thin, solid-state cooling. Frore's AirJet Mini and Mini Slim can both generate 1,750 Pascals of back pressure, but they're also larger and thicker than the XMC-2400, measuring 2.8mm and 2.5mm thick, respectively. Frore showed off its technology by hacking it into a MacBook Air, and according to The Verge, it pushed out heat and led to improved sustained performance.

As Housholder puts it, xMEMS' technology is more flexible since its far thinner, and manufacturers can also choose from side- and top-venting options. He expects the XMC-2400 to cost under $10 per chip, and that "four to five" existing partners will get their hands on it by the end of the year. Other manufacturers can snag it in the first quarter of 2025. xMEMS' fabrication partners, TSMC and Bosch, can easily switch from building its speakers today to constructing micro-cooling chips tomorrow, Housholder says. There's no need to change equipment or production lines.

As devices like the iPad Pro juggle extreme thinness with powerful performance, the need for some sort of ultra-thin active cooling solution is clear. We can't escape physics, after all—that's something I learned when my MacBook Air died on Apple's own campus. While we still need to see the xMEMS micro-cooling chip in action to form any sort of judgment, theoretically, it could end up being indispensable in the future.