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A 30-Picowatt Processor For Sensors

Posted by timothy on from the just-think-what-a-AA-battery-could-do dept.

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.

5 of 93 comments (clear)

  1. Theoretically... by seanadams.com · · Score: 5, Insightful


    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.

    1. Re:Theoretically... by hvm2hvm · · Score: 3, Insightful

      And they are right. I don't work with watts every day so I don't understand exactly what 30pW mean. This is how the human brain works: comparisons with other things in life. You know that a Hummer is big because most other vehicles are smaller. A sky scraper is big only when compared to a 10 story building (which in turn you must compare to your own height). Stop picking on these details, it's pointless. And BTW, your condescending way of saying "I am smart because I can understand the real way of measuring power" is just stupid. Grow up.

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      ics
  2. The art of compromise by EmbeddedJanitor · · Score: 2, Insightful
    Processors such as the Microchip PIC10F are down to the nanoWatts level. That is more than fine for many/most purposes. These things cost well less than a buck each and include various peripherals. They can operate in a wide range of voltages and temperatures.

    These 30pW sleep mode CPUs will allow things to go to the next level of minaturisation, but will need reduced cost and will need to prove that they are reliable.

    There is a huge issue with power consumption vs stability. Basically, each bit in a CPU holds a certain charge. When you flip the bit and discharge/charge the bit then you're dumping energy which is what results in much of a CPU's power consumption. Storing smaller charge per bit reduces power consumption. But reducing the charge also reduces stability and makes those bits more prone to EMF, leakage etc. Before I'd trust these gizzmos I'd want to see how well they operate at temperature extremes, near microwave ovens, cell phones etc.

    Making them work in a lab is one thing, in the real world is quite another.

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    Engineering is the art of compromise.
  3. If it's 30-picowatt in Sleep mode... by Siriaan · · Score: 3, Insightful

    Surely it's a bit of a stretch to call it a "30-picowatt Processor"?

  4. Yes by dreamchaser · · Score: 1, Insightful

    It's a lot like my 0 watt lightbulb. It uses 100 watts when turned on, and zero when turned off.