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HP Creates First Hybrid Memristor Chip
An anonymous reader writes "HP researchers have built the first functioning hybrid memristor-transistor chip. Lead researcher Stanley Williams and his team built the very first memristor — the '4th fundamental element' of integrated circuits after resistors, capacitors and inductors — back in April. Memristors can remember their resistance, leading to novel electronic capabilities. The new FPGA circuit uses memristors to perform tasks normally carried out by (many more) transistors and is therefore smaller, more power efficient and cheaper to make, HP says. Memristors could also turn out to be a more compact, faster alternative to flash memory."
Does anyone know what size features the chip was etched at? um? nm? That might give a clue how close it is to being used in other products.
The memristors made in April were 50 nm wide
In general there are two ways to store data (at least in a RAM type memory module). You can either use a capacitor (like DRAM) or a flip flop (SRAM). The problem with a capacitor is that it looses it's charge after a certain amount of time, and has to be refreshed (which is why DRAM is relatively slow). A flip-flop can be used to store one bit, but in order to do that two separate latches are needed. One latch has 2-4 gates each having 2-8 transistors. All of a sudden there are over a dozen transistors used to store one but. A memristior does not actually help any calculations, it just hopefully make storing data much more efficent
Who is the idiot modding this as Funny? A SPICE model is an engineering tool used to diagram circuits. It is NOT related to any of the Spice Girls!!! :p
Where's the link to MetaModerate?? grrr...
Attention all planets of the Solar Federation! We have assumed control! - Neil Peart
I think you could build one from components if you had data about the memristance function. Start with a voltage controlled resistance element (Gxxx) connected to the two exposed terminals. Add a hidden element of a current controlled current source, sensing on the VCR element, injecting current into a hidden capacitor. The voltage on that capacitor is proportional to the total charge that has passed through the memristor device. The exposed VCR element senses voltage on the hidden capacitor, and uses an interpolated table of resistance vs voltage rather than a linear relationship.
That doesn't capture the hysteretic behavior of the current devices, which stop integrating at the some limiting points, but it's a starting point. You could add such behavior with a few more hidden components (back-to-back ideal zeners across the hidden cap, for example), though getting the right behavior might be a little tricky.
I believe what they mean is that the memristor is "fundamental" in that it provides a symmetrical link between electric charge and magnetic flux. A resistor is the link between current and voltage, a capacitor - voltage and charge, an inductor - current and magnetic flux, and a memristor - magnetic flux and charge. I think. I'm sure someone with a better grounding in electromagnetic physics can clarify this a bit.