Computer smaller than a grain of rice
The Phoenix processor is miniscule at 915 x 915µm2, and boasts ultra-low operating voltage and a unique standby mode that results in an average power consumption of only 500pW. (Consider that 1pW is the average power consumption of a single human cell.) Blaauw explained why Phoenix's extreme energy efficiency is so important: 'As you shrink down in size, the percentage of the system tends to be dominated by the battery.
"It's actually not hard to make chips small, but it is hard to make them low power.
We could have very small chips, but we'd still end up with really large batteries."
This line of 'smart dust' devices includes computers equipped with imagers (with motion detection), temperature sensors, and pressure sensors.
One key application for this line of smart sensors lies in personal security and information, its inventors say.
The solar system allows the computer to work under indoor lights without ever having to be charged.
With a 1mm2 solar cell producing 20nW, the device can harvest enough energy under ambient light to run perpetually,' the team say.
The device's standby power consumption is 2nA.
That's about a million times less power than the average mobile phone consumes while on standby, or the comparative difference between the thickness of a sheet of paper and the length of a football field.
There are currently three different systems in the M3 family, focusing on several different applications: sensing temperature, pressure, and taking images.
"Down the road we want these sensors to be able to talk to one another," says Blaauw, "and we're currently working to extend their range to about 20m."