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F-RAM
Ferroelectric random-access memory has similar contruction like DRAM but instead of a dielectric layer, it contains a thin ferroelectric film to achieve non-volatility. F-RAM retains its data memory when power is shut off or interrupted. F-RAM was proposed by a graduate student Dudley Allen Buck but the development began in late 1980s and work was done in 1991.
F-RAM has extremely high endurance, ultra low power consumption , etc. but low storage density and high cost. -
PROM
Programmable read-only memory, was invented in 1956 by Wen Tsing Chow, is a form of digital memory where the setting of each bit is locked by a fuse or antifuse. Its first use was to store the targeting constants in the Atlas E/F ICBM's airborne digital computer. It's a one-time programmable memory.
It frequently uses in video game consoles, mobile phones, RFID tags, implantable medical devices, HDMI... -
PRAM
PRAM or Phase-change memory exploit the unique behavior of chalcogenide glass. In 1969, Charles Sie published a dissertation, at Iowa State University that both described and demonstrated the feasibility of a phase change memory device by integrating chalcogenide film with a diode array. PRAM is much faster than the common flash memory, from 500 to 1,000 times faster, and it also uses up to one half the power. -
EPROM
Erasable programmable read only memory was invented by Dov Frohman of Intel in 1971. EPROM can be erased by exposing it to strong ultraviolet light source. It has a small quartz window which admits UV light for erasure. Once you erase it, everything will be erased and you can't keep the old data. Old PC BIOS used EPROM. -
EEPROM
Because the EPROM is too expensive to make and it doesn't keep old data when erase, EPROM is replaced by EEPROM-Electrically Erasable Programmable Read-Only Memory. In 1978, George Perlegos at Intel developed the Intel 2816, which was built on earlier EPROM technology, but used a thin gate oxide layer so that the chip could erase its own bits without requiring a UV source. EEPROM can be programmed and erased electrically using field electron emission and you can edit data on it. -
MRAM
Magnetoresistive RAM is under development since European scientists (Albert Fert and Peter Grünberg) discovered the "giant magnetoresistive effect" in thin-film structures. MRAM stores data by magnetic storage elements. It has the same reading and writing principle as magnetic core memory. Advantages are high density, least expensive...