• Skip to main content
  • Skip to primary sidebar
  • Skip to secondary sidebar
  • Skip to footer

Computer Notes

Library
    • Computer Fundamental
    • Computer Memory
    • DBMS Tutorial
    • Operating System
    • Computer Networking
    • C Programming
    • C++ Programming
    • Java Programming
    • C# Programming
    • SQL Tutorial
    • Management Tutorial
    • Computer Graphics
    • Compiler Design
    • Style Sheet
    • JavaScript Tutorial
    • Html Tutorial
    • Wordpress Tutorial
    • Python Tutorial
    • PHP Tutorial
    • JSP Tutorial
    • AngularJS Tutorial
    • Data Structures
    • E Commerce Tutorial
    • Visual Basic
    • Structs2 Tutorial
    • Digital Electronics
    • Internet Terms
    • Servlet Tutorial
    • Software Engineering
    • Interviews Questions
    • Basic Terms
    • Troubleshooting
Menu

Header Right

Home » Fundamental » Memory » What is Flash Memory? – Definition
Next →
← Prev

What is Flash Memory? – Definition

By Dinesh Thakur

Definition: Flash memory (Known as Flash Storage) is a type of non-volatile storage memory that can be written or programmed in units called “Sector” or a “Block.” Flash Memory is EEPROM (Electronically Erasable Programmable Read-Only Memory) means that it can retain its contents when the power supply removed, but whose contents can be quickly erased and rewritten at the byte level by applying a short pulse of higher voltage. This is called flash erasure, hence the name. Flash memory is currently both too expensive and too slow to serve as main memory.

Flash memory (sometimes called “Flash RAM”) is a distinct EEPROM that can read block-wise. Typically the sizes of the block can be from hundreds to thousands of bits. Flash Storage block can be divided into at least two logical sub-blocks.

Flash memory mostly used in consumer storage devices, and for networking technology. It commonly found in mobile phones, USB flash drives, tablet computers, and embedded controllers.

Flash memory is often used to hold control code such as the basic input/output system (BIOS) in a personal computer. When BIOS needs to be changed (rewritten), the flash memory can be written to in block (rather than byte) sizes, making it easy to update. On the other hand, flash memory is not used as random access memory (RAM) because RAM needs to be addressable at the byte (not the block) level.

Flash memories are based on Floating-Gate Transistors. Floating gate transistors are used in memory to store a bit of information. Flash memories are used in the device to store a large number of songs, images, files, software, and video for an extended period,etc.

We’ll be covering the following topics in this tutorial:

  • History Flash Memory
  • Types of Flash Memory
  • Limitation of Flash Memory

History Flash Memory

In 1980’s Flash memory as invented by Fujio Masuoka, while working in Toshiba. In 1988, Intel introduced NOR flash memory chip having random access to memory location. These NOR chips were a well-suited replacement for older ROM chips. In 1989, with more improvement, NAND flash memory was introduced by Toshiba. NAND flash memory is similar to a Hard disk with more data storage capacity. After that, there has been a rapid growth in flash memory over the years passes.

Flash memory is an electronic chip that retains its stored data without any power. Flash memory is different from RAM.RAM is volatile memory, needs electricity and power to maintain its content. However, flash memory does not require the power for holding data. Flash memory was used in many devices like in form SD card, Pen-drive (moveable storage), camera card and video card, and so forth. Flash memory gives faster access to data content as compared to hard disk. In hard-disk, disk rotation takes time to move on the particular cylinder, track or sector.However,in a flash, no rotating time disc has created a barrier for fast access.

Types of Flash Memory

Flash memory is available in two kinds NAND Flash and NOR Flash Memory. NAND and NOR flash memory both have different architecture and used for specific purpose.

NAND Flash Memory

In today is an environment where all devices require high data density, faster speed access and cost-effective chip for data storage. NAND memory has needed less chip area hence more data density. NAND Memory used the concept of the block to access and erases the data. Each block contains the different size of pages various from bytes. MMU (Memory Management Unit) helps NAND to the first page the content or copied into RAM and then executed.

NOR Flash Memory

In the circuit of flash memory, memory cells are connected in parallel. It provides random or sequentially access memory. Data Reading process for NOR and RAM are similar. We can execute the code directly from NOR without copying into RAM. NOR memory ideal for runs small code instructions program. It referred to Code-storage applications. It used for low-density applications.

NOR flash provides support to bad block management. Bad block in memory is handled by controller devices to improve functionality.

We can use the combination of both NOR and NAND memory. NOR (software ROM) used for instruction execution,and NAND used for non-volatile data storage.

Limitation of Flash Memory

Although Flash memory gives many advantages, yet it has some flaw.

1) We can quickly read or programmed a byte at a time, but we cannot erase a byte or word. It can delete data in blocks at a time.

2) Bit flipping: Bit Flipping problem is more occur in NAND memory as compare to NOR. In Bit Flipping, a bit get reversed and create errors. For checking and correcting the bit error (EDC/ECC) detection and error correction code are implemented.

3) Bad block: Bad block are the blocks which can’t be used for storage. If scanning system gets fails to check and recognize bad block in memory. Then reliability of system gets reduced.

4) Usage of NOR and NAND memory: NOR is easy to use. Just connect it and use it. However, NAND not used like that. NAND has I/O interface and requires a driver for performing any operation. Read operation from NOR do not need any driver.

You’ll also like:

  1. What is Secondary Memory? – Definition
  2. What is Non-Volatile Random Access Memory (NVRAM)? – Definition
  3. What is virtual memory? – Definition
  4. What is ECC Memory? – Definition
  5. What is Primary Memory? – Definition
Next →
← Prev
Like/Subscribe us for latest updates     

About Dinesh Thakur
Dinesh ThakurDinesh Thakur holds an B.C.A, MCDBA, MCSD certifications. Dinesh authors the hugely popular Computer Notes blog. Where he writes how-to guides around Computer fundamental , computer software, Computer programming, and web apps.

Dinesh Thakur is a Freelance Writer who helps different clients from all over the globe. Dinesh has written over 500+ blogs, 30+ eBooks, and 10000+ Posts for all types of clients.


For any type of query or something that you think is missing, please feel free to Contact us.


Primary Sidebar

Computer Memory

Computer Memory

    • Computer - Memory
    • Computer - Types of Memory
    • Computer - RAM
    • Computer - Types of RAM
    • Computer - ROM
    • Computer - RAM Vs ROM
    • Computer - Associative Memory
    • Computer - SemiConductor Memory
    • Computer - Primary Memory
    • Computer - Auxiliary Memory
    • Computer - Flash Memory
    • Computer - EPROM
    • Computer - Secondary Memory
    • Computer - Sequential Access Memory
    • Computer - EEPROM
    • Computer - Bubble Memory
    • Computer - DDRAM Vs FPMDRAM
    • Computer - SDRAM
    • Computer - DRAM
    • Computer - VRAM
    • Computer - ECC Memory
    • Computer - PC RAM
    • Computer - NVRAM
    • Computer - Register

Computer Devices

    • Computer - Input/Output Devices
    • Computer - Printer
    • Computer - Laser Printer
    • Computer - Hard Drive
    • Computer - Dot-Matrix Printer
    • Computer - Impact and Non-Impact
    • Computer - Storage Devices
    • Computer - Primary Storage
    • Computer - Types of Storage
    • Computer - Line Printer

Other Terms

    • Computer - Interrupt
    • Computer - Classify Storage Devices
    • Computer - CISC and RISC
    • Computer - Access Method
    • Computer - Memory Mapping
    • Computer - OMR
    • Computer - Access Time
    • Computer - Types of integrity
    • Computer - Buffer
    • Computer - Associative Cache
    • Computer - RAM Parity
    • Computer - Disk Cache
    • Computer - Disk Controller
    • Computer - Cycle Time
    • Computer - IDE
    • Computer - RAM Disk
    • Computer - Cartridge Hard Disk
    • Computer - DPI
    • Computer - Fatal Error
    • Computer - Install HDD/SSD
    • Computer - Input Technologies
    • Computer - OCR

Binary Number

  • CO - EBCDIC
  • CO - ASCII Code
  • CO - Bit
  • CO - ASCII
  • CO - BCD Numbers
  • CO - Binary Numbers
  • CO - Byte
  • CO - Bits and Bytes
  • CO - Machine Code

Other Links

  • Computer Memory - PDF Version

Footer

Basic Course

  • Computer Fundamental
  • Computer Networking
  • Operating System
  • Database System
  • Computer Graphics
  • Management System
  • Software Engineering
  • Digital Electronics
  • Electronic Commerce
  • Compiler Design
  • Troubleshooting

Programming

  • Java Programming
  • Structured Query (SQL)
  • C Programming
  • C++ Programming
  • Visual Basic
  • Data Structures
  • Struts 2
  • Java Servlet
  • C# Programming
  • Basic Terms
  • Interviews

World Wide Web

  • Internet
  • Java Script
  • HTML Language
  • Cascading Style Sheet
  • Java Server Pages
  • Wordpress
  • PHP
  • Python Tutorial
  • AngularJS
  • Troubleshooting

 About Us |  Contact Us |  FAQ

Dinesh Thakur is a Technology Columinist and founder of Computer Notes.

Copyright © 2023. All Rights Reserved.