Phoenix chip needs 30,000 times less power when in sleep mode than comparable chips
Engineers at the University of Michigan have developed a new microchip that uses 30,000 times less power in sleep mode and ten times less power when working than other comparable chips on the market.
The processor (called The Phoenix Processor) set a low-power record by consuming only 30 picowatts when in sleep mode. A picowatt is one-trillionth of a watt. The researchers say that theoretically the low power requirements of the chip when in sleep mode would allow a standard watch battery to power the processor for 263 years.
The processor isn’t any smaller physically than other chips on the market, which routinely measure the same one square millimeter size or even smaller. What is unique about the Phoenix is that its thin-film battery is the same size as the Phoenix chip.
In most cases the batteries used with processors are much larger than the processor itself making the overall size of the device much larger. Professor David Blaauw of the Department of Electrical Engineering and Computer Science said in a statement, “Low power consumption allows us to reduce battery size and thereby overall system size. Our system, including the battery, is projected to be 1,000 times smaller than the smallest known sensing system today. It could allow for a host of new sensor applications.”
The engineers see the Phoenix chip being used in devices like medical implants, environment monitors and surveillance equipment.
To get the huge power savings the engineers employed old processor technology and used much smaller power gates that let smaller amounts of electricity leak past the power gates when in sleep mode. The trade off for the much smaller power gates is that they severely limit processing power of the chip.
To remedy the performance loss the researchers run the Phoenix at a higher operating voltage of about 20% greater than needed when the chip is awake. Despite the higher power sent to the chip when awake it still consumes only 0.5 volts. By comparison the Intel Atom processor needs 1.1V to operate.
The chip defaults to sleep mode and is woke up by a low-power timer every ten minutes for 1/10th of a second to run a set of 2,000 instructions. These instructions include checking the sensor for new data, processing the data and storing it before going back to sleep.
