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A 30-Picowatt Processor For Sensors
Roland Piquepaille writes "University of Michigan (U-M) researchers have developed an ultra low power microchip which 'uses 30,000 times less power in sleep mode and 10 times less in active mode than comparable chips now on the market.' It only consumes 30 picowatts in sleep mode, which means that a simple watch battery could power the chip for more than 200 years. Of course, this is not a processor for your next computer. It is designed for sensor-based devices such as medical implants, environment monitors or surveillance equipment. However, the design is very clever." Roland's blog has some more information, including a die picture of the chip, known as the Phoenix.
What's with all these idiots who think "theoretically" is a synonym for "not really"? This gem in particular:
"Theoretically, the energy stored in a watch battery would be enough to run the Phoenix for 263 years."
Note that it's carefully worded to say "the energy stored in.." not to that a watch battery actually _could_ do this. Because it couldn't. The battery's internal resistance and chemical processes would cause it to drain itself long before you'd ever consume a meaningful portion of that energy.
Only in very specialized applications where you have extremely weak, but continuous sources of power, could you realize any benefit to a picowatt vs a nanowatt of consumption. For batteries or supercaps, the power source will self-discharge at a much higher rate anyway.