Low power, tiny chip could see connected smart devices go battery-free
Everything needs to be online nowadays, from vending machines to smart speakers, but that connectivity costs in terms of bulk and energy use. Now researchers have come up with a chip that gets devices connected with 5,000 times less power draw than normal.
For manufacturers developing small, low-powered Internet of Things devices, that's a significant step forward. It means that hardware can be made smaller, and use less energy, while still pinging the web for updates and information.
The chip itself is smaller than a grain of rice and consumes just 28 microwatts of power, a tiny fraction of a standard Wi-Fi radio. It can transmit data at a rate of 2 megabits a second (enough for decent quality video) at a range of up to 21 meters (69 ft).
This feat of engineering is achieved through a technique called backscattering, which encodes new data on to incoming Wi-Fi signals before transmitting them on somewhere else. This sort of piggybacking uses up far less energy, and that means a lot more flexibility for device makers.
"This Wi-Fi radio is low enough power that we can now start thinking about new application spaces where you no longer need to plug IoT devices into the wall," said computer engineering professor Patrick Mercier from UC San Diego, who helped lead the work. "This could unleash smaller, fully wireless IoT setups. It could also allow you to connect devices that are not currently connected – things that cannot meet the power demands of current Wi-Fi radios, like a smoke alarm – and not have a huge burden on battery replacement."
You might not think that having an Amazon Echo plugged in or changing the batteries every month on a security camera is all that much of a burden, but as the number of devices increases, so does the maintenance and energy required.
Imagine a smart speaker that instead of being plugged in could be carried around the house, and using a coin battery that could last for years. Large batteries, frequent recharging, or separate power supplies would no longer be needed.
The way the researchers see it, this could enable smart home setups to go fully wireless and even battery-free in some cases. The tiny Wi-Fi chip could also find a place in wearables in the future, though it will of course take some time to evolve from laboratory experiment to a component that can be commercially used.
The work is being presented at the International Solid-State Circuits Conference (ISSCC) 2020, February 16 to 20, in San Francisco.
Source: UC San Diego