The race for ever more powerful mobile processors may be keeping Qualcomm, Nvidia, and Samsung occupied for now, but ARM is focusing on another goal – designing ultra-low power processors. After years of research and various internal designs, the microchip company is now developing a new low-power microcontroller core, which will be quite slow compared with the processors that we’re more familiar with.
Low power chips aren’t anything particularly new – a few companies already offer sub 2V microcontrollers for battery powered devices. But in order to take advantage of minute power sources, ARM intends to push the voltage requirements right down to the threshold of where a transistor can be turned on and off. However, there’s a trade-off with much slower performance.
The core will be working down at the bare minimum voltage of traditional transistors, meaning operating voltages of just 0.3-0.6 volts, and will be clocked in in the low kilohertz range, so you’re more likely to see this one ticking over as a 50 kHz chip, rather than a 2 GHz multi-core processor.
Don’t expect to see these chips powering a new range of super battery efficient smartphones, but such a development has interesting implications for low power communication devices and the Internet of Things. Speaking with a group of UK journalists, Mike Muller, chief technology officer at ARM, talked about the strategies required for processing small amounts of data and transmitting these small packets, and how such a device could be powered by energy scavenged from the local environment.
Normally, the best strategy is to do processing as fast as possible and then go to sleep for as long as possible—get in and get out. But for energy scavenging, it can be different.
As these chips could be made to work with limited power supplies, especially if they have to scavenge energy from other devices or sources, there might not always be the energy available to transmit information on demand. For the Internet of Things to become a reality, these microprocessors need to be able to cope with unreliable supplies, and that’s an unexplored area when it comes to processor technology.
Remember the “ambient backscatter” concept we covered a couple of weeks ago, whereby devices can communicate by piggybacking on background radio waves? Well ARM’s new chip seems to be based on the idea that it could potentially be powered by weaker power sources such as this, allowing for some level of computer processing without requiring a large main source or a battery for a power supply.
Although ARM’s chip is going to be too slow for most of the applications that we’re used to, a few kilohertz is all that’s required to send and process small packets of data, including text, and it could even be fast enough for voice interactions as well. The main use for such a chip is likely to be found in making everyday devices a little smarter, from simple things like being able to transmit the location of your misplaced keys, to building “smart homes” that can respond to user input, or in self-sustaining data transmission networks for businesses.
With the push into wearable technology attracting a lot of attention lately, very low power chips could provide us with simpler and smarter ways to communicate with other devices, and with each other, in the not too distant future.