Different Types of Computer Memory
Computer Memory is primary computer hardware storage. It could store files temporarily or permanently. Computer Memory usually operates at a high speed. One example is the Random-access memory or RAM. Computer memory links to an addressable semiconductor memory. Volatile and Non-volatile are two types of semiconductor memory. Volatile memory is a type of computer memory wherein electrical energy keeps and maintains the stored information. RAM is a common example of volatile memory. Non-volatile memory is a type of computer memory wherein electrical energy is not required to keep and maintain stored information. ROM and flash memory are types of non-volatile memory.
DRAM and SRAM
DRAM or Dynamic random-access memory is a type of random-access memory. Its function is to store basic unit information of data in the separate capacitor under an integrated circuit or microchip. Static random-access memory or SRAM is a type of semiconductor memory. Its function is to store basic unit of information using a bistable flip-flop. There are some main differences between DRAM and SRAM. One difference is that DRAMs run for a computer’s main memory while SRAMs run for CPU cache. SRAMS are also faster however, more expensive than DRAMs.
EEPROM is short for Electrically Erasable Programmable read-only memory. It is a unique type of non-volatile memory. Its function is to store small amounts of data while allowing individual bytes to be erased or reprogrammed in computers and other electronic devices. EEPROMs systemize in a range of floating-gate transistors. Exposing a chip to ultra-violet light lets EEPROM delete bytes.
F-RAM or Ferroelectric RAM is a type of non-volatile random-access memory that is the same in construction with DRAM. F-RAM however, uses a ferroelectric layer rather than dielectric layer to reach non-volatility. It provides the same function as a flash memory. It has a faster write performance, a greater maximum number of write-erase cycles and lower power usage than flash memory. The downside of F-RAM is it has limited storage capacity and density and more expensive than flash memory.
Flash Memory is a type of non-volatile electronic memory storage. Information in flash memory could be electrically erased and reprogrammed. Flash memory was developed based on EEPROM. There are two main types of flash memory. NAND type of flash memory came after the NAND logic gate. NAND flash memories are read and written in blocks. NAND types are usually in forms of USB flash drives, memory cards and other solid-state storage devices. The second type of flash memory is the NOR flash memory. NOR flash memory came after NOR logic gate. NOR flash memories can write, erase and read separately a single machine word or bytes. NAND and NOR have distinguishing characteristics. They have a different connection to their individual memory and interface provider for reading and writing memory.
EPROM is short for Erasable Programmable Read-only Memory. EPROM is in the form of a microchip that can store data when power is switched off. The transparent fused quartz window wherein the silicon chip is visible can easily recognize EPROMs. It allows exposure to UV light during erasing process. A device called the PROM programmer or PROM burner enables EPROMs to write and erase contents. EPROM storage location consists of a single field-effect transistor. The field-effect transistor uses an electric field to power the electrical conductivity channel of a carrier in a semiconductor material. EPROMs come in different sizes and storage capacity.
ROM and PROM
ROM or read-only memory is a type of non-volatile memory. ROMs function as storage for firmware. Firmware is a type of software connected to a specific hardware. ROM only refers to memory that is hard-wired. Mask ROM is a type of ROM created after the invention of an integrated circuit. Mask ROM are made up of a network of word lines and bit lines. Transistor switches connect them together. Mask ROM encodes the data physically in the circuit. Most types of ROMs recently are already semiconductor based. PROM or programmable read-only memory is a type of ROM. PROM is a digital form memory where fuse or anti-fuse locks the position of each bit. PROM stores data that is permanent. ROM is, however, different from PROM. In ROM, the data are already built-in during manufacture while PROMS had no data after manufacture. PROMS allow a company to program data into a blank PROM chip using a PROM programmer. Microcontrollers, video games, and mobile phones store their programs in PROMs.