Electronic Memory

Digital Memory

The term "memory", meaning "primary storage" or "main memory", is often associated with addressable semiconductor memory, i.e. integrated circuits consisting of silicon-based transistors, used for example as primary storage but also other purposes in computers and other digital electronic devices.

Electronic Memory is simply storage of data in the form of binary digits representing values on any form of media. Most commonly it is used to describe RAM (Random Access Memory) which are modules that you install on the motherboard of a laptop or desktop computer and store information for you to use and that allows your computer to work using electricity. It CAN refer to Hard Drives which can be internal or external and store information magnetically (still in the form of binary digits) on metal platters that spin very fast and are accessed by a needle reader (or multiple needles). The other type of electronic memory is ROM (Read Only Memory) which is static (semi permanent) and contains information (still in binary digits) that tell your computer that it is a computer and how to route data. The ROM is a CMOS Chip that can be reprogrammed (upgraded) but this is dangerous if you don't do it right or know what you are doing.

There are two main kinds of semiconductor memory, volatile and non-volatile.

  • RAM (Random Access Memory), is both readable and writable. It is volatile, which means it requires power in order to retain its contents. ( The term volatile is borrowed from chemistry, where it refers to something that evaporates. )

    Computer programs and data are normally stored in disk files when they are not in use. When a program is run (executed), the program and the data it manipulates are loaded from disk into RAM, which is about 1,000,000 times faster than disk. This greatly improves speed when the same data is accessed repeatedly.

  • ROM (Read-Only Memory) is not generally writable. The original ROMs were set to a specific content at the factory and could never be written again.

    Today, we use EEPROM, or electronically erasable programmable ROMs, such as Flash memory. EEPROMS are writable, but not as easily as RAM. There are special procedures to altering the contents of a EEPROM. The important feature of ROM and EEPROM is that it is non-volatile, so it retains its content even when the power is cut.

    Non-volatile memory is used to store firmware, which is essentially software that stays in memory when the power is off. Firmware makes it possible for computers to start when the power is turned on (cold boot), and allows small and embedded devices which are often powered down to function. The boot sequence cannot be started from disk, since reading a program from disk requires a program! Hence, there must be a minimal amount of program code in memory when the power comes on to start the boot sequence. In a personal computer, the firmware, sometimes called BIOS (Basic Input/Output System or Built-In Operating System), initializes the hardware and loads the first part of the operating system from disk. From there, the operating system takes over.

DRAM - Memory Manufacturers

Elite Semiconductor Memory Technology Inc. 'ESMT' {SDRAM-DDR SDRAM-EDO DRAM-SGRAM IC Manufacturer}
Etron Technology Inc. {DRAM-SDRAM-SGDRAM ICs}
Fujitsu Microelectronics Inc. {SDRAM - DRAM IC Manufacturer}
Integrated Silicon Solutions Inc. 'ISSI' {DRAM IC Manufacturer}
Irvine Sensors Corp. {Chip Stacks-SDRAM-DDR DRAM-EDO}
Mitsubishi Electronics America Inc. {DRAM-SDRAM IC Manufacturer}
MoSys Inc. "Monolithic System Technology, Inc." {DRAM - SGRAM - PBSRAM ICs}
Nanya Technology Corp. {DRAM-SDRAM-EDO-FPM-DDR SDRAM}
Nippon Steel Semiconductor Corp. {DRAM IC Manufacturer}
Panasonic Industrial Co. {DRAM IC Manufacturer}
Rambus Corp. {RDRAM IC Manufacturer}
Renesas Technology Corp
Samsung Semiconductor Inc. {SDRAM-DDR SDRAM-RAMbus DRAM-EDO Fast page DRAM}
Toshiba America Electronic Components Inc. {SGRAM, DRAM, FCRAM}
Vanguard International Semiconductor 'VIS' {SDRAM - DRAM ICs}

SRAM - Memory Manufacturers

AeroFlex {RADHard SRAM IC Manufacturer}
Aptos Semiconductor Corp. "Integrated Silicon Solutions, Inc." {SRAM IC Manufacturer}
Benchmarq "TI" {SRAM IC Manufacturer}
Brilliance Semiconductor Inc. {SRAM ICs}
Cypress Products. {SRAM IC Manufacturer}
Dallas Semiconductor Corp 'Maxim' {SRAM}
GSI Technology
Holtek Semiconductor Inc.
Honeywell {Radiation Hardened SRAM ICs}
Integrated Device Technology, Inc. 'IDT' {SRAM, 4Mb, 9Mb, 18 Mb ZBT SRAM}
Integrated Silicon Solutions Inc. 'ISSI' {SRAM IC Manufacturer}
Logic Devices {SRAM ICs}
Micron {SRAM IC Manufacturer}
Mitsubishi Electronics America Inc. {SRAM}
NEC {Low Power SRAM, Asynchronous SRAM, Synchronous SRAM, ZBT SRAM, DDR II, QDR II SRAM}
Pyramid Semiconductor {Commercial/Industrial, Military/883}
Renesas Technology Corp {SRAM, 18 Mb ZBT SRAM}
Sharp Electronic Corp. {SRAM}
Sony {SRAM IC Manufacturer}
Toshiba America Electronic Components Inc. {SRAM IC Manufacturer}
UTMC Microelectronic Systems Inc., see Aeroflex {Rad-Hard SRAM ICs}
Winbond Electronics Corp. {SRAM IC Manufacturer}
ZMD America Inc. {SRAM / nvSRAM IC Manufacturer. Commercial, Industrial, Automotive, Military Temperature Grades,PDIP,SOP,TSOP,BGA,PLCC Packages. nvRAM devices}

IBS Electronics is a distributor for many industrial memory manufacturers of reliable NAND Flash & DRAM modules storage solutions for Mobile Devices, Computers, Embedded, Automotive, IoT, Networking & Telecom and more.