Technology
What makes it tick
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conductor, allowing electrons to flow, and an insulator, or non-conductor, which stops the flow of electrons. The genius comes in where, using this principle, a "gate" or "gated valve" can be created that either allows or disallows electron flow through the simple application of an electrical charge to the gate material. This forms the binary logic gate – yes, where the "1's" and "0's" (1 = flow, or "on" and 0 = no flow or "off") you've heard so much about come in. It is this technology upon which nearly all electronics known today is grounded.
The advantages to "the gate" are too numerous to name in this short article.
While you may not believe in the significance of a simple little gadget that opens or closes, it is when many of them are placed together that gives this unassuming little valve mechanism its crowning glory. Most any electric appliance today has some sort of logic circuit built into it – from your alarm clock to your coffee maker; from your hair dryer to your toaster. And that’s not even counting the larger things – your refrigerator, your conventional oven, your microwave oven, etc. If it does something – goes on and off at a particular time or gets up to a particular temperature, chances are it contains some form of logic circuit.
Whenever there's an upside, you know there's a downside. The downside to the integrated circuit is its heat generation property. Carver Mead, Cal Tech professor emeritus and the one who first coined the phrase "Moore's Law," presented a paper at the 2013 ISSCC (International Solid-State Circuits Conference), showing how the more IC’s on the board, the more of the “usable energy” (the power required to operate the circuit) “leaks” or is wasted. This means that at the present level of density (the number of IC’s we can squeeze onto a circuit board), almost half of the power taken in by the circuit is wasted. The waste is heat. Everything comes at a cost, and that's the cost of the semiconductor. Having so many of those miniscule gates opening and closing creates friction – ergo, heat. But relief may be on the way.
Researchers at Stanford University created, what they call, the "Neurogrid," a computer circuit board that has the ability to imitate the behavior of the human brain through its network of one million human neurons. Carbon nanotubes, of which the Neurogrid is composed, provide heat dissipation much more efficiently than silicone, so the component runs cooler. This is definitely a lifesaver for the industry, because silicone-based semiconductors have reached the upper limits of their expandability. Something needs to be done in order to carry the future past the silicone limitation threshold.
So, Moore's law no longer holds true. Aside from a pessimistic prediction by Bob Colwell, former chief technology architect at Intel, that Moore's Law is going to "fizzle-out" by 2022, because companies won't be interested in racing toward the next level of computational speed, there are still scientists out there searching for the next breakthrough. It would certainly be a disappointing future if Colwell was right. But I believe that he just wanted to share the status that Moore, a co-founder of Intel, by having a famous prophecy. Moore's forecast was based, however, on empirical data – whereas Colwell's is pure speculation. Lucky for us…
Go, Stanford!
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Broadcast Beat Magazine / Sep-Dec, 2014