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Fast access, unlimited write cycles, and you don't lose any data if the power trips out half-way through. Sounds perfect for the write cache on a hard drive, or the journal on a file-system that has such a thing.
NEC has made more progress in its development of a flip-flop switch for system-on-chips that offers near zero electricity use in standby states by using magnetic RAM technology. Magnetic RAM uses the direction of a magnetic field in a memory cell to indicate a binary one or zero, and is one of the candidates posited to succeed …
If these things can operate fast enough to replace every register/memory-element in your CPU then you could make the CPU fully static and be able to power it down between instructions. You'd only need to keep the interrupt circuitry and timers warm. That'd apply just as well to mobile phones as any other device.
"NEC says that SOCs have CMOS gate logic circuits which need constant clock-synchronised power to preserve their state. A component called a data flip-flop is involved here along with static RAM (SRAM)."
OK I know this is a pedantic point, but the preservation of state does not require a clock -- most CMOS logic can have its clock speed reduced all the way to zero -- it consumes only "leakage power". Admittedly this is still quite a large proportion of the total power consumed by a typical SoC.
"with unlimited write endurance"
That's the killer feature. Making the storage medium much more like RAM than short lived Flash opens up the huge opportunity to have instant on computers and mobile devices. I wish my Sky box was instant on.
If they could make similar densities and costing as Flash (or even just half the density as Flash) I wouldn't touch Flash memory. We badly need a memory that is as high density as Flash but as reusable as RAM. Its the holy grail of electronics.
Memristors are the other big hope, but sadly it looks like they also suffer from write endurance problems.
Writing a file to Flash is one thing. But try using it like RAM. A counter in Flash memory even updated only at 1khz would be dead within under 2 minutes. :(
Fast access, unlimited write cycles, and you don't lose any data if the power trips out half-way through. Sounds perfect for the write cache on a hard drive, or the journal on a file-system that has such a thing.
If you go waving a large magnet near it and fudge the flip-flops?
I expect it's the same as a hard drive in that respect. It doesn't seem to be a problem in practice.
If you are describing a fully static system, then no, clocks are not required to keep the state. However a fully static system requires more transistors per state storage "bit" that latch the bit as a 1 or 0 with feedback to keep the bit latched, despite low levels of leakage that occur. This type of memory is SRAM.
Nowadays, most systems are dynamic (including computer RAM; hence the term DRAM). This requires far fewer transistors per bit and hence allows for smaller chips, or chips that do more stuff. Unfortunately there is always a small leakage from the bits, so they need to be read and written back peridically to refresh them and this requires clocks.
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