CHAPTER 7 Storage 6.ppt

1、CHAPTER 7 Storage,PC Cards,2,Disk Drive vs. Flash Memory,Read / Write (+) Lost cost per bit (-) Mechanical movement (SPM & VCM) (-) High power consumption (10-15W) (-) Heavy weight compared to flash,Read / Program / Erase (+) Random Access (+) Non-volatile (+) Low Power Consumption (2W) (-) Erase be

2、fore Write (-) Erasing operation in the unit of block (not page) (-) Maximum # of erase operations per cell (-) High cost per bit,3,History of Flash Memory,4,NAND Flash Memory Program/Erase,F-N tunneling Give a higher voltage and electrons are trapped through gate into floating gate transistor.,5,Fl

3、ash Memory Comparison,NOR (Code Executable in Place like Memory) Fast read and slow write NAND (Data-storage) Fast write and lower cost,6,NAND Flash Non-Volatile Flash Cards,Various Standard Memory Cards,7,Functional Block Diagram for SAMSUNG K9K8G08U0M NAND Flash,8,NAND Flash Technology,9,Compariso

4、n for Different Memory Types,10,Hybrid Hard Disk (HDD),Seagates ReadyDrive HDD Prototype of Samsung & Seagate for Labtop (WinHEC conf. 2006) 128 MB NAND Flash Memory in hard disk Store frequently accessed sectors of data for quick reads(e.g., FAT table) Flash is used to make less frequent disk power down and up. Advantages Reliability, Power-Efficient, and Improved Performance Experiment Run Office Applications Spun up every three and four minutes 10% power saving,11,Seagates 5400 RPM Hybrid Hard Drive,160 GB of regular perpend