The same solid-state chips used to make headphones and mini-speakers could soon be used to keep high-end smartphones from overheating.
xMEMS Labs is a Californian company specializing in piezoelectric micro-electro-mechanical systems — tiny chips that move air by applying voltage to a piezo actuator layer, which bends a piece of silicon back and forth.
The xMEMS technology already appears in a range of headphones, such as Creative’s Aurvana Earbuds, replacing the coil/magnet technology traditionally found in speakers and headphones.
However, the xMEMS chips are about to appear in a range of new products, including premium earbuds, smart watches and even as cooling devices in smartphones.
Premium Headphones
The solid-state MEMS technology offers a much cleaner sound than traditional headphones, according to Mike Householder, vice president of marketing and business development for xMEMS.
The company’s Cypress silicon will more accurately reproduce the amplitude of the original audio signal than traditional headphones, he claims. He also adds that the solid-state chip will “ring down” more quickly, unlike vibrating headphones or speakers which carry on making a sound even after the sound signal stops.
“Legacy dynamic drivers typically don’t ring down very quickly,” said Householder. “So there’s a lot of bleed into the next audio signal.”
Householder demonstrated this with a pair of prototype headphones, the same chips from which will be used in premium earbuds from well-known manufacturers later this year. Although it’s hard to draw any firm conclusions from a quick demo in a noisy hotel suite, they certainly made The Eagles’ Hotel California sound very bright and precise to my ears.
“Everyone’s really excited about this product, because not only does it give you really enhanced clarity and smaller size, but the speed and precision of the transducer is going to help ANC,” he said, referring to active noise cancelling technology.
MEMS Speakers
The MEMS technology isn’t purely confined to headphones. The company has evolved the hardware to make it loud enough to use for loudspeakers, albeit not at volumes that are going to blow your socks off.
The limited volume the current generation of hardware is capable of delivering means the first xMEMS speakers are being targeted at devices such as smart watches or smart glasses, where you only need relatively quiet audio.
Smart glasses makers — of which there are dozens here at CES 2025 — are particularly interested in the technology, Householder claims, because the millimeter-thick chips are easier to fit into glasses arms than conventional speakers, and because they’re able to make long, thin speakers that better fit the shape of the arms.
Cooling Chips
Headphones and speakers aren’t the only applications for the MEMS chips. They could soon be used to cool components in high-end smartphones and other hardware where it’s difficult to install fans or other cooling systems.
As the chips are only a millimeter thick, they can be used for “spot cooling”, applied directly to the component that is running hot, without significantly increasing the thickness of the device.
“We’re good at applying cooling to small, isolated spaces,” Householder said. “With our micro-cooling, you can basically put us dead center in the phone, if you had to,” he said, with only a very thin duct required to deliver airflow.
That could allow smartphone manufacturers to unleash the full power of today’s chips, which they can’t do currently because of over-heating concerns. “All the phone guys are telling us ‘we are thermal constrained’,” said Householder. “There are things that the Qualcomm SOC can do that we’re just simply turning off, because we can’t meet thermal constraints.”
The xMEMS XMC-2400 µCooling chip will go into production later this year and could appear in a wide range of products, including smartphones, tablets, gaming handhelds and even in data centers.
