Which of the following is a type of nonvolatile memory that can be erased?
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PROM: Pronounced prom, an acronym for programmable read-only memory. A PROM is a memory chip on which data can be written only once. Once a program has been written onto a PROM, it remains there forever. Unlike RAM, PROMs retain their contents when the computer is turned off. The difference between a PROM and a ROM (read-only memory) is that a PROM is manufactured as blank memory, whereas a ROM is programmed during the manufacturing process. To write data onto a PROM chip, you need a special device called a PROM programmer or PROM burner. The process of programming a PROM is sometimes called burning the PROM. An EPROM (erasable programmable read-only memory) is a special type of PROM that can be erased by exposing it to ultraviolet light. Once it is erased, it can be reprogrammed. An EEPROM is similar to a PROM, but requires only electricity to be erased. Show
EPROM: Acronym for erasable programmable read-only memory, and pronounced e-prom, EPROM is a special type of memory that retains its contents until it is exposed to ultraviolet light. The ultraviolet light clears its contents, making it possible to reprogram the memory. To write to and erase an EPROM, you need a special device called a PROM programmer or PROM burner. An EPROM differs from a PROM in that a PROM can be written to only once and cannot be erased. EPROMs are used widely in personal computers because they enable the manufacturer to change the contents of the PROM before the computer is actually shipped. This means that bugs can be removed and new versions installed shortly before delivery. A note on EPROM technology: The bits of an EPROM are programmed by injecting electrons with an elevated voltage into the floating gate of a field-effect transistor where a 0 bit is desired. The electrons trapped there cause that transistor to conduct, reading as 0. To erase the EPROM, the trapped electrons are given enough energy to escape the floating gate by bombarding the chip with ultraviolet radiation through the quartz window. To prevent slow erasure over a period of years from sunlight and fluorescent lights, this quartz window is covered with an opaque label in normal use. EEPROM: Acronym for electrically erasable programmable read-only memory. Pronounced double-e-prom or e-e-prom, an EEPROM is a special type of PROM that can be erased by exposing it to an electrical charge. Like other types of PROM, EEPROM retains its contents even when the power is turned off. Also like other types of ROM, EEPROM is not as fast as RAM. EEPROM is similar to flash memory (sometimes called flash EEPROM). The principal difference is that EEPROM requires data to be written or erased one byte at a time whereas flash memory allows data to be written or erased in blocks. This makes flash memory faster. FRAM: Short for Ferroelectric Random Access Memory, a type of non-volatile memory developed by Ramtron International Corporation. FRAM combines the access speed of DRAM and SRAM with the non-volatility of ROM. Because of its high speed, it is replacing EEPROM in many devices. The term FRAM itself is a trademark of Ramtron. NVRAM: Abbreviation of Non-Volatile Random Access Memory, a type of memory that retains its contents when power is turned off. One type of NVRAM is SRAM that is made non-volatile by connecting it to a constant power source such as a battery. Another type of NVRAM uses EEPROM chips to save its contents when power is turned off. In this case, NVRAM is composed of a combination of SRAM and EEPROM chips. Bubble Memory: A type of non-volatile memory composed of a thin layer of material that can be easily magnetized in only one direction. When a magnetic field is applied to circular area of this substance that is not magnetized in the same direction, the area is reduced to a smaller circle, or bubble. It was once widely believed that bubble memory would become one of the leading memory technologies, but these promises have not been fulfilled. Other non-volatile memory types, such as EEPROM, are both faster and less expensive than bubble memory. Flash Memory: A special type of EEPROM that can be erased and reprogrammed in blocks instead of one byte at a time. Many modern PCs have their BIOS stored on a flash memory chip so that it can easily be updated if necessary. Such a BIOS is sometimes called a flash BIOS. Flash memory is also popular in modems because it enables the modem manufacturer to support new protocols as they become standardized. Non-volatile storage (NVS) is a broad collection of technologies and devices that do not require a continuous power supply to retain data or program code persistently on a short- or long-term basis. Non-volatile storage technologies and devices vary widely in the manner and speed in which they transfer and retrieve data, whether communicating with an application, microprocessor or other type of device. They can also vary significantly in terms of cost, capacity, endurance and latency. Non-volatile storage is often categorized by the following two system types:
Most of today's solid-state drives (SSDs) are equipped with NAND flash memory chips. An SSD is considered an electrically addressed system because it uses electrical mechanisms to write and read data. As a result, the SSD can deliver faster speeds and lower latency than a mechanically addressed system such as an HDD. However, the per-byte price to store data in a flash-based SSD is generally higher than the per-byte cost of an HDD or tape drive. In addition, flash SSDs can sustain only a limited number of write cycles before they wear out. What are non-volatile storage examples?Three common examples of NVS devices that persistently store data are tape drives, HDDs and SSDs. The term non-volatile storage also applies to the semiconductor chips that store data or controller program code within devices such as SSDs, HDDs, tape drives and memory modules. Many types of non-volatile memory chips are in use today. For instance, the SSDs in enterprise and personal computer systems typically use NAND flash memory chips to store data. The chips are also used in USB sticks and memory cards in consumer devices such as mobile telephones and digital cameras. NOR flash memory chips commonly store controller code in storage drives and personal electronic devices. Volatile vs. non-volatile storage devicesThe key difference between volatile and non-volatile storage devices is whether or not they are able to retain data in the absence of a power supply. Volatile storage devices lose data when power is interrupted or turned off. By contrast, non-volatile devices are able to retain data regardless of the status of the power source. Common types of volatile storage include static random access memory (SRAM) and dynamic random access memory (DRAM). Manufacturers may add battery power to a volatile memory device to enable it to persistently store data or controller code, but if the battery fails or is removed, the data is still lost. Enterprise and consumer computing systems often use a mix of volatile and non-volatile memory technologies, and each memory type has advantages and disadvantages. For instance, SRAM is faster than DRAM and well suited to high-speed caching, but it is expensive to manufacture. DRAM is less expensive to produce and requires less power than SRAM, and manufacturers often use it to store program code that a computer requires immediate access to in order to operate efficiently.  By contrast, non-volatile storage such as HDDs and SSDs is slower than SRAM and DRAM but is cheaper to produce. Manufacturers commonly use NAND flash memory to store data persistently in business systems and consumer devices. Storage devices such as flash-based SSDs access data at a block level, whereas SRAM and DRAM support random data access at a byte level. Like NAND, NOR flash is less expensive to produce than volatile SRAM and DRAM. NOR flash costs more than NAND flash, but it can read data faster than NAND, making it a common choice for booting consumer and embedded devices and for storing controller code in SSDs, HDDs and tape drives. NOR flash is generally not used for long-term data storage due to its poor endurance. Trends and future directionsManufacturers are working on additional types of non-volatile storage to try to lower the per-bit cost to store data and program code, improve performance, increase endurance levels and reduce power consumption. For instance, manufacturers developed 3D NAND flash technology in response to physical scaling limitations of two-dimensional, or planar, NAND flash. 3D NAND can deliver higher densities at a lower cost per bit by vertically stacking memory cells, rather than using a single layer of cells. Over the years, manufacturers have also been increasing the number of bits per cell in NAND flash storage.
By increasing the number of bits per cell, flash-based SSDs can hold more data, resulting in lower prices, reduced power consumption and smaller footprints. Multi-cell configurations are also used in conjunction with 3D NAND to increase capacities even further. In addition, manufacturers are actively working on penta-level cell (PLC) flash, which squeezes five bits per cell, although it could still be several years before PLC devices hit the market. Manufacturers have also been working on storage solutions that bridge the gap between traditional volatile system memory and flash-based SSDs, providing an additional tier in the storage hierarchy. The most notable effort has been the 3D XPoint project co-developed by Intel Corp. and Micron Technology Inc. 3D XPoint offers higher throughput, lower latency, greater density and improved endurance over NAND flash technology. Intel was the first to offer products based on 3D XPoint, shipping them under the brand name Optane, which includes a line of SSDs and persistent memory modules intended for data center use. Persistent memory modules are also known as storage class memory. Non-volatile memory express (NVMe) technology has also proved to be a game-changer in the storage industry. NVMe makes it possible to connect flash-based SSDs directly to a computer's PCI Express (PCIe) bus, rather than connecting through Serial Attached SCSI (SAS) or Serial ATA (SATA) interfaces. These older technologies were built for slower HDDs and cannot take full advantage of the SSD's capabilities. NVMe can also be used in conjunction with newer options such as Optane SSDs, further accelerating performance and reducing latency and power consumption. NVMe offers a more streamlined command set to process input/output (I/O) requests with PCIe-based SSDs than the Small Computer System Interface (SCSI) command set does with SAS drives or the analog telephone adapter (ATA) command set does with SATA drives. The success of NVMe led to the development of NVMe over Fabrics (NVMe-oF), a specification that was created to support the use of the NVMe command set when transferring data between SSDs and other systems over a network fabric such as Ethernet, Fibre Channel or InfiniBand. According to NVM Express Inc., 90% of the NVMe-oF protocol is the same as basic NVMe. Emerging non-volatile storage technologies currently in development or in limited use include phase-change memory (PCM), ferroelectric RAM (FRAM or FeRAM), magnetoresistive RAM (MRAM), resistive RAM (RRAM or ReRAM) and spin-transfer torque magnetoresistive RAM (STT-MRAM or STT-RAM). Which of the following is a type of nonvolatile memory that can be erased electronically and rewritten similar to EEPROM group of answer choices?Flash memory is an electronic non-volatile computer memory storage medium that can be electrically erased and reprogrammed. The two main types of flash memory, NOR flash and NAND flash, are named for the NOR and NAND logic gates.
Is a type of nonvolatile memory that can be erased electronically and rewritten?Flash memory is a type of nonvolatile memory that can be erased electronically and rewritten.
Can nonNon-volatile memory such as the electrically erasable programmable read only memory (EEPROM) is a device for holding data. Data stored inside the memory can be read or erased a multiple of times, and furthermore, the data is retained even after power is turned off.
Which of the following memory is nonvolatile memory?non-volatile memory include read-only memory (see ROM), flash memory, most types of magnetic computer storage devices (e.g. hard disks, floppy discs and magnetic tape), optical discs, and early computer storage methods such as paper tape and punched cards.
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