1. Presented By: Rob Douglas, Alex Alexandrov
Flash Memory
Presented By:
Rob Douglas, Alex Alexandrov

2. Points of Discussion Flash Memory Generalities History of Flash Memory
Construction & Properties
History of Flash Memory
NOR & NAND Architectures
Optimizations
Standardization
New Developments & Future of Flash
Closing Statements

3. Flash Memory
A type of EEPROM (Electrically-Erasable Programmable Read-Only Memory)
Non-volatile, solid state technology
Relatively limited lifespan
Information is stored in an array of memory cells made from floating-gate (FG) transistors

4. Flash Memory Packaged inside a memory card:
Extremely durable
Can withstand intense pressure
Immersion in water
Better kinetic shock resistance than hard disks
Average power requirements range from 5V-12V

5. Flash Memory Cell

6. History of Flash Memory
Invented by Fujio Masuoka while he was working for Toshiba in the early 1980s
First introduced at the 1984 International Electron Devices Meeting in San Francisco

7. Manufacturers of Flash

8. NOR Flash Memory Developed to replace read only memory
Full address and data buses allow random access to any memory location
Can access any memory cell
Slow sequential access

9. NAND Flash Memory Developed to replace hard disks
Sequential-accessed command and data registers replace the external bus of NOR
Decreases chip real estate
Can only access pages
Faster sequential access

10. Optimizations Wear levelling Bad block management
Counting writes & dynamically remapping blocks
Bad block management
Write verification and remapping bad sectors
Multi-Level Cell technology
Memory cells store more than one bit

11. Standardization Part of the reason for the success of Flash memory
Open NAND Flash Interface Working Group developed standard low-level interface
Standard pinout
Standard command set for reading, writing, and erasing NAND flash chips
Mechanism for self-identification

12. New Developments AND Flash DINOR (DIvided bit-line NOR) Flash
Bit line replaced with embedded diffusion line to reduce cell size
Low power dissipation (3V)
DINOR (DIvided bit-line NOR) Flash
Attempts to reduce the chip real estate compared to conventional NOR
Low power dissipation (3V), sector erase, high data transfer rate

13. Future of Flash Memory
Continues to be among the most aggressively scaled electronic technologies
Memory cell size minimum of 20 nm expected to be met in 2010
May be replaced by Phase-Change RAM or other emerging technologies

14. In Closing…
One of the most popular alternatives for portable device storage
Aggressive advances are still being made

15. References Wikipedia - Flash Memory How Stuff Works - Flash Memory

16. Questions?