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Magnetic Transistor Could Cut Power Consumption and Make Chips Reprogrammable
ananyo writes "Transistors, the simple switches at the heart of all modern electronics, generally use a tiny voltage to toggle between 'on' and 'off.' The voltage approach is highly reliable and easy to miniaturize, but has its disadvantages. First, keeping the voltage on requires power, which drives up the energy consumption of the microchip. Second, transistors must be hard-wired into the chips and can't be reconfigured, which means computers need dedicated circuitry for all their functions. Now, researchers have made a type of transistor that can be switched with magnetism. The device could cut the power consumption of computers, cell phones and other electronics — and allow chips themselves to be 'reprogrammed' (abstract)."
Been so for 25 years. It's called FLASH memory.
They mean the transistors are programmable. If you can change the chip logic, you can get custom behaviours at top speed. Flash is for firmware, but doesn't change the chip itself. This stuff is awesome if it can be made to be as fast as a regular transistor. OTOH magnetism itself is a bit of a worry, as the chip could get wiped quite easily.
Do it yourself, because no one else will do it yourself. [beta blockade 10-17 Feb]
programmable gate arrays that can operate in the gigahertz. some specially made for networking
one that requires voltage to keep it on, one that requires voltage to keep it off (P channel vs N channel FET's), ones that require current levels to keep it on and off (npn and pnp BJT's)
so to say
"First, keeping the voltage on requires power"
is a broad statement, yea something that uses power requires power
Then
"Second, transistors must be hard-wired into the chips and can't be reconfigured"
well yea, but we have long established configurations of transistors that can be reconfigured to suit needs, its called programable logic and spans the life of PAL's, GAL's, CLPD's, and upto FPGA's
so, what exactly are you trying to tell me other than magnets can drop power consumption since they have a physical state memory, we already know that from core memory.
Core !! Old as the hills !! So old, it has come back around !! Probably some shit unix time wrap failure !!
It's a standard field effect transistor, except the gate can hold a magnetic charge on its own, with no voltage applied. You only need to apply a charge to change its state. It actually looks sort of like a flash cell, except as the gate of a transistor.
However, it's made with indium antimonide, which apparently doesn't work well with existing fabrication methods. And I have to wonder what the switching times on it would be - if it can handle the multi-gigahertz frequencies in modern processors.
The whole "reconfigurable" bit is journalist bullshit. Pay no attention to it.
You could say the same thing about transistors vs vacuum tubes.
Not really. Magnetism trails off with the cube of the distance, rather than the square of the distance.
Sorry, but microprogrammed instruction codes are still several layers above the transistor switch level.
mu-Metal works better than iron. It has 80-100 times better shielding capability. It's also lighter (kinda a big thing for space use...)
Chaos maximizes locally around me.
EEPROMs as flash RAM or firmware is old, very old. But the idea of a processor being field reprogrammable *is* new. It's so new, nobody has anything that would benefit yet. Think of something like Cisco booting based off the startup config, then optimizing the processors based on the config. Port 2 shutdown? Divert the gates to process something else. Want to be able to turn anything on and off without any delays? Then consider dynamic memory allocations. Not dynamic storage, the way everyone thinks, but looking at whether there are 64 bit requirements, and if not, programming it as parallel 32-bit CPUs for extra speed, and if 64-bit is requiring, booting up in 64-bit mode. Got an idle encryption ASIC? Now you have another general processor.
You claim it is common, but has anyone ever released a CPU that changed dynamically? Rather than optimizing code for the CPU, optmize the CPU for the code. I see this being biggest in the area where ASICs are biggest, networking gear. Need more hardware encryption? Need more QoS profiles?
Learn to love Alaska
To keep a magnetic field going (small as it might be) you need to have a current flowing...
And that's why I have wires and batteries connected to all my fridge magnets...
You don't need a current to sustain the magnetic domain in something like a hard disk, which is the impression I get of what this technology is about.
Not sure you understand how a Faraday cage works - they are not powered.
If you can change the chip logic, you can get custom behaviours at top speed.
That's what we thought about FPGAs, but it didn't quite work out that way. Using this technology won't change that, it will just allow us to make better FPGAs.
Reprogramming an FPGA is slow (many switches to reconfigure, usually serially), which means it would only increase overal performance if you can use the custom function long enough, and it only works if you don't have to switch functions too often.
Writing software for an FPGA is difficult (it's more logic design than software) and requires specialized software. Reconfiguring it in a wrong way could damage the silicon (though modern devices and software have some protections and checks). So any custom functionality would come in the form of libraries, written by specialists.
The amount of extra interconnect and transistors needed to make a CPU reprogrammable are also significant, resulting in higher die area (and thus cost), lesser transistor density (=slower speed), and overall higher energy consumption.
The result of all this is that FPGAs are only used in very custom hardware (usually low volume), with the programming remaining largely static, only to be altered when there are bugs found or improvements needed (once a month or less).
The article says the switching depends on the direction of the magnetic field, so that sounds like it has to be sustained.
However, it could be possible to use magnetic nanoparticles to provide that magnetic field, which is the solution proposed in the second half of the article. A stronger-than-normal electric field could be used to rotate those magnets. The problem is that building such a structure is very difficult. A bottom-up nanotech approach combined with our current top-down lithography would introduce far too many contaminants. Trying to get a nanoparticle solution to go exactly where you want it is extremely difficult, especially due to the high surface forces that make nanoparticles like to stick to things. The difficulty of using a traditional top-down approach is making the nanoparticles able to rotate. There would need to be multiple types of resist used, likely, one to define the shape, and the other to be removed at the end to provide spacing during fabrication. The high surface forces as mentioned previously would also pose a big problem. Nanocrystals lack the stability given by long-range order and, especially with sub-10nm crystals, can have unique crystal structures due to this large stress. In order to mainain stability and not try to merge with neighboring crystals, there either needs to be an electrostatic barrier or physical barrier. Because it's impossible to keep something passively balanced with a electric or magnetic field, there would need to be the additional complexity of a pivot placed at the necessary angle. It's possible that something like graphene could be used to provide lubercatoin of the pivots, but this means that both the graphene and magnet would have to have compatible crystal structures so that the depostion growth grows with a known crystal orrientation (for knowing where to place the pivot).
On the other hand, this technology could be very useful with current technology in MEMS (microelectromechanical systems). A field of these transistors could be used to very accurately know the position of a magnet, in, say, an actuator, or on a spring for an accellerometer.