NOR Flash
NAND Flash
High-speed Access
Yes
Yes
Page-Mode Data Access
No
Yes
Random Byte Level Access
Yes
No
Typical Uses
Cell Phones
PDAs
BIOS Storage for PCs
Digital Cameras
Networking Device Memory
MP3 players
Solid State Disk Drives
Set-Top Boxes
Industrial Storage
(and pictures) remains saved on the flash storage device. The ability to retain data is
key for flash memory applications such as digital film for digital cameras, cell phones,
PDAs and other transportable devices.
There are two major technologies of flash memory: NOR and NAND. Each
technology has its strengths that make it ideal for different kinds of applications, as
summarized in the table below:
4.1 NOR FLASH MEMORY
NOR, named after the specific data mapping technology (Not OR), is a high-speed
Flash technology. NOR Flash memory provides high-speed random-access
capabilities, being able to read and write data in specific locations in the memory
without having to access the memory in sequential mode. Unlike NAND Flash, NOR
Flash allows the retrieval of data as small as a single byte. NOR Flash excels in
applications where data is randomly retrieved or written. NOR is most often found
built into cellular phones and PDAs and is also used in computers to store the BIOS
program that runs to provide the start-up functionality.
4.2 NAND FLASH MEMORY
NAND Flash was invented after NOR Flash, and is named after the specific mapping
technology used for data (Not AND). NAND Flash memory reads and writes in high-
speed, sequential mode, handling data in small, block sizes (“pages”). NAND Flash can
retrieve or write data as single pages, but cannot retrieve individual bytes like NOR Flash.
NAND Flash memory is commonly found in solid-state hard drives, audio and video
digital media devices, television set-top boxes, digital cameras and other devices
where data is generally written or read sequentially.
C O M M I T T E D TO M E M O R Y
FLASH MEMORY
KINGSTON TECHNOLOGY
6
kingston.com/flash
Kingston Flash cards
were rated the best
in read and write
performance by
dpreview.com.
