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Electromechanical Switches Could Reduce Future Computers' Cooling Needs
Earthquake Retrofit writes "Science Daily is reporting that researchers at Case Western Reserve University have taken the first step to building a computer capable of operating in extreme heat. Te-Hao Lee, Swarup Bhunia and Mehran Mehregany have made electromechanical switches — building blocks of circuits — that can take twice the heat that would render electronic transistors useless. 'The group used electron beam lithography and sulfur hexafluoride gas to etch the switches, just a few hundred nanometers in size, out of silicon carbide. The result is a switch that has no discernable leakage and no loss of power in testing at 500 degrees Celsius. A pair of switches were used to make an inverter, which was able to switch on and off 500,000 times per second, performing computation each cycle. The switches, however, began to break down after 2 billion cycles and in a manner the researchers do not yet fully understand. ... Whether they can reach the point of competing with faster transistors for office and home and even supercomputing, remains to be seen. The researchers point out that with the ability to handle much higher heat, the need for costly and space-consuming cooling systems would be eliminated.'"
Miniaturized relays are interesting, but an inverter which operates at 0.0005 Ghz is less interesting. Somehow I don't think we'll be seeing this replace electronics anytime soon. (well, except in lithium battery microcontrollers :-) ). Although it would be interesting technology for a steampunk novel.
Will the components still function after the water sprinklers have activated? Narrow minded safety officers and tight fisted bureaucrats are still going to put water sprinklers in data centers.
Every mans' island needs an ocean; choose your ocean carefully.
How will they keep the keyboards from burning your fingertips?
Sometimes the light at the end of the tunnel is the headlight of an oncoming train.
Hundreds of nanometers is rather larger then the current tech 32nm. These are going to have to get quite a bit smaller, faster, and more durable before they stand a chance. A two billion cycle limit is the worst part i think, my cpu did that in the last .66 seconds.
I tried to tell them that tubes and transistors were just a fad. Relays were good enough for the Z4 and they're good enough for us. These kids and their newfangled gadgets...
Warning: this article may contain humor, sarcasm, parody, and perhaps even irony. Read at your own risk.
Both attributes that the military would like.
Can anyone clarify how this performs switching? As far as I can see, they do not elaborate on the source of switching power. Solenoids at that scale would be rather challenging. Electrostatics seems unlikely. Perhaps the actual power source is a lot of reprogrammed Maxwell's Demons.
From scarped cliff or quarried stone she cries "A thousand types are gone, I care for nothing, no not one."
... is easily explained. There is a flaw in the design. Someone apparently made the "wear out expiration" register signed instead of unsigned.
now we need to go OSS in diesel cars
you just cant keep flexing it forever and ever, it eventually breaks
Kind of like the "rod logic" in Diamond Age by Neal Stephenson.
There are two sources of heat in modern semiconductor CPU's.
One is leakage, the heat generated by current times resistance squared in transistors that are off.
The higher current that is related to the clock speed is the heat generated by transistors that are turned on using the same current times resistance squared.
To keep the on current at a bare minimum, transistors are paired with one on and one off so the current through the pair should be zero except for leakage. The current flows when they are clocked and the capacitance (stored voltage) of the wire between transistors and gate capacitance of the MOSFET it drives supplies current during switching.
How does this no heat switch avoid the current of switching the capacitance between the switches. From what I can tell is this part is able to handle higher temperatures. I do not see it as a no power (no heat generated) device.
Silicon Nitride has much higher resistance than most metals. Due to the resistance and temperature resistance, it is often used as hot surface ignition in gas appliances. Current through the switches will create heat. It is unavoidable.
At it's current speed of 0.000.5 GHZ clock speed, I can believe the current power consumption is very low. How does this stack up to an Atom CPU clocked at 0.000.5 GHZ?
The truth shall set you free!
TFA gives no value in kJ. It talks about temperature, but temperature != heat.
This is a research idea that MAY be useful, the demise of CMOS silicon has been highly exaggerated.
From the summary:
"an inverter, which was able to switch on and off 500,000 times per second" -> 500kHz is not so great
"however, began to break down after 2 billion cycles" or about 1 second at current processor speeds. That increases to 4000 seconds at 500kHz, or a little more than an hour.
Also, we can put billions of error free transistors on a chip for a few dollars. THAT is the real hurdle that nothing else has been able to clear yet. We will likely be with silicon for a while after it stops shrinking for this reason.
Whether they can reach the point of competing with faster transistors for office and home and even supercomputing, remains to be seen.
Well you know what they say, illegitimus non carborundum.
So in other words it'll last 4000 seconds. Little over an hour. Perhaps notalot of use just yet except perhaps in
short lived weapons - missiles and suchlike. But they don't need heat tolerance.
A gate input acts like a capacitor. Something in the output that feeds it has to limit the inrush current. Whatever that is generates the heat. If the resistance isn't supplied by a transistor, it will be supplied by the wires. The basic formula that describes the heat generated by a gate doesn't change.
What may change is that the circuit may become less damped. That could lead to problems with ringing.
So, I'm not convinced that these mechanical switches will have any advantage on heat generation and they could have characteristics (like lack of damping) that might slow them down.
On the other hand, maybe they are less affected by radiation. ;-) We can speculate like crazy until someone actually builds a system and takes measurements.
Great, now we'll have computers that operate twice as hot, meaning that they are twice as likely to ignite their batteries.
"It's the height of ridiculousness to say for those 9 lines you get hundreds of millions."
Nobody's going to use this for desktop CPUs. The whole point is that the switches work at 500 degrees C, where silicon doesn't. This technology would be used for embedded control in extremely hostile environments, where 500 kHz would be just fine. The article names the inside of a jet engine and the surface of Venus as examples.
Visit the
I do test circuit hardware design and we use standard relays all over the board, for switching bits of circuitry into and out of contact with an integrated circuit we're testing. We use mechanical relays because of the same reasons they say: zero leakage current when they're open, and extremely low resistance when they're closed, which semiconductor switches just can't equal. The problem is the lifetime of the relays, so we have to socket them all (which, when you're building a board with 500 relays on it, is a significant time and money sink) and replace them pretty often on high-running parts (some of our parts have been in high-volume production for 20 years.) Plus they're big and take up the majority of the board. Having a device that's tiny and can last a billion cycles would be completely awesome.
Nostalgia's not what it used to be.
The combination stove, space heater, blowtorch computer! I imagine we would still desire some amount of cooling or at least shielding from the heat but this is an interesting development.
iburnaga.blogspot.com
The venerable 6502 was also the heart of the VIC 20. A slightly modified/improved version was used in what was the most ubiquitous personal computer, the Commodore 64. Although running at only 1Mhz, most of its instructions executed in less than 3 clock cycles, making for some pretty efficient and fast ML code.
Willie...
I suggest the "Mark 0.000001", in honor of that famous relay computer, the Mark I.
#naabhaprzrag, #sverubfr-000, #agi-fcbafberq, negvpyr[pynff*=' negvpyr-ary-'] { qvfcynl: abar !vzcbegnag; }
for precisely the reasons outlined here. they operate very well at very high temperatures.
anything operating on a mechanical basis will have a finite lifetime. a billion cycles sounds like a lot, but not when everything is switching 10 million times a second.
so these things will never work as a replacement for transistors.
making things smaller will always result in greater leakage. there might be salvation in quantum transistors. however, see tunneling.
also see mems.
Absolute statements are never true
Mechanical devices are more durable then silicon? Who would have thought.. other then Captain Obvious of cousre.
---- Booth was a patriot ----
...that and a Direct X. frame limiter for those games that love to give 240 un-needed frames per second and have no cap option.
If you are right and they are using relatively high DC for switching, the rapid wearout is quite unsurprising.
From scarped cliff or quarried stone she cries "A thousand types are gone, I care for nothing, no not one."
one of the main reasons transistors were sought out is to eliminate constant maintenance on electromechanical devices
so how long is one of these going to last at 500 degrees C running at ~500khz ?
The engineers took their cue from English inventor Charles Babbage, who built a steam-driven machine to calculate mathematical tables in the 1830s. The group applied nanotechnology to make switches fit today's ever-smaller computing platforms.
So they want to build an computer with electromechanical switches - and they take their inspiration from Babbages's steam-driven machines instead of the computers with electromechanical switches that Konrad Zuse build?
Fandroids hate facts.
The venerable 6502 was also the heart of the VIC 20. A slightly modified/improved version was used in what was the most ubiquitous personal computer, the Commodore 64. Although running at only 1Mhz, most of its instructions executed in less than 3 clock cycles, making for some pretty efficient and fast ML code.
So? Today even simple processors can finish several instructions per clock cycle (even though each instruction could take longer). A processor with these mini-relays could still run circles around the 6502 even with a slower clock.
Fandroids hate facts.
First we have flash memory can that only be written to N number of times, and now they're building a cpu that can only do N computations?
Seems like something interesting for planetary exploration where standard CPUs on a probe would be rendered useless in a matter of hours. Much as the equipment sent to Venus.
It is not more durable.
Just that regular silicon transistors do not work at high temperature. They leak so much current that you can't tell if it is leaking or the transistor is on.
Not yet mentioned is the opportunity to use MEM switches for filters, modulators, phase comparators and a few other useful devices. The basic principle is synchronous rectification, whereby switches of a bridge open and close in sequence to rectify an incoming signal. A key advantage is elimination of L-C components and the ability to generate and filter arbitrary waveforms.
Why Vacuum Tubes?
...if he were still alive. He built his (and the world's) first programmable binary computer with program storage, the Z3, from old mechanical relays.
As the article states, these would be ideal for processors that operated on the surfaces of Mercury and Venus. While a probe on the surface of Mercury could probably get away with good (but very large and heavy) heat shielding, Venus especially has always been a problem for probes and the Soviet Venera probes that delivered images of Venus' surface lasted only somehwere around 57 minutes before failing. A probe based on this technology, i.e. a working high temperature design, could last much longer.
MEMS switches have been around for a while now in the ATE and RF markets:
http://www.memsindustrygroup.org/i4a/pages/index.cfm?pageid=3759