All articles with unsourced statements Articles with unsourced statements from October Commons category link from Wikidata Wikipedia articles with GND identifiers. It is an array of floating-gate transistors individually programmed by an electronic device that supplies higher voltages than those normally used in digital circuits. Initially, it was thought that the EPROM would be too expensive for mass production use and that it would be confined to development only.
Computer memory that can retrieve stored data after a power supply has been turned off and back on is called non-volatile. This efprom larger capacity devices to introduce a “signature mode”, allowing the manufacturer and device to be identified by the EPROM programmer. Paper data storage Drum memory Magnetic-core memory Plated wire memory Core rope memory s Thin-film memory Disk pack Twistor memory - Bubble memory - Floppy disk Erasure, however, has to be accomplished by non-electrical methods, since the gate electrode is not accessible electrically. The erasing window must be kept covered with an opaque label to prevent accidental erasure by the UV found in sunlight or camera flashes. While parts of the same size from different manufacturers are compatible in read mode, different manufacturers added different and sometimes multiple programming modes leading to subtle differences in the programming process. To retrieve data from the EPROM, the address represented by the values at the address pins of the EPROM is decoded and used to connect one word usually an 8-bit byte of storage to the output buffer amplifiers. Stored charge on these isolated gates eeeprom their properties. It was soon found that small-volume production was economical with EPROM parts, particularly when the advantage of rapid upgrades of firmware was considered. For large volumes of parts thousands of pieces or moremask-programmed ROMs are the lowest cost devices to produce.Ī control gate electrode is deposited and further oxide covers it. The process takes several minutes for UV lamps of convenient sizes sunlight would erase a chip in weeks, and indoor fluorescent lighting over several years.
In effect, the stored charge on the floating gate allows the threshold voltage of the transistor to be programmed.Īn insulating layer of oxide is grown over the channel, then a conductive silicon or aluminum gate electrode is deposited, and a further thick layer of oxide is deposited over eerpom gate electrode.ĮPROM programming is slow compared to other forms of memory. The switching state of the field-effect transistor is controlled by the voltage on the control gate of the transistor. Photons of the UV light cause ionization within the silicon oxide, which allow the stored charge on the floating gate to dissipate.īy using this site, you agree to the Terms of Use and Privacy Policy. However, these require many weeks lead time to make, since the artwork for an IC mask layer must be altered to store data on the ROMs. Non-volatile memory Integrated circuits Computer memory.
ST Microelectronics – datasheet pdfīecause higher-density parts have little exposed oxide between the layers of interconnects and gate, ultraviolet erasing eeprkm less practical for very large memories. Like EPROM chips, such microcontrollers came in windowed expensive versions that were used for debugging and program development. MF1 STMicroelectronics EEPROM DISC BY SGS 11/95 datasheet, inventory, & pricing. The M is a, bit UV erasable and electrically programmable memory EPROM. Accessing individual bytes from an address transition or from power-up (chip enable. The device is organized into 64K words by.
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