SSD (SSD (Solid State Drive) Solid State Drive)

GUIDED BY :

Mr. ASHWANI KR. PANDEYB.TECH, M.TECHAssociate Professor

DEPARTMENT OF ELECTRONICS AND COMMUNICATIONS

PRESENTED BY :

SAURABH KUMAR

ContentsContents•HistoryHistory•Solid State DrivesSolid State Drives•NAND Flash MemoryNAND Flash Memory•SSD ElementsSSD Elements 1. SSD Controller1. SSD Controller 2. SSD Flash2. SSD Flash 3. SSD Interfaces3. SSD Interfaces•SSD Storage SchemeSSD Storage Scheme

• SSD ArchitectureSSD Architecture• SSD Around usSSD Around us• Inter x25 SSD- an Inter x25 SSD- an

ExampleExample• Benefits of SSDBenefits of SSD• SSD vs. HDDSSD vs. HDD• ApplicationApplication

HistoryHistory• Storage Devices are evolved as the use of

machines is increasing. Punch Cards (in 1940s). Magnetic Tapes/Drives (in 1950s). Hard Drives. Solid State Drives.

Solid State Drive(SSD)Solid State Drive(SSD)

• SSD is an PC storage device that SSD is an PC storage device that uses Solid State memory to store uses Solid State memory to store information.information.

• SSD uses non volatile NAND Flash SSD uses non volatile NAND Flash Memory , which enables it to Memory , which enables it to retain data when the power retain data when the power is removed.is removed.

NAND Flash MemoryNAND Flash Memory• NAND Flash Memory is the key NAND Flash Memory is the key

component of SSD.component of SSD.• It is a specific type of EEPROM chip.It is a specific type of EEPROM chip.• It has a grid of columns and rows with a It has a grid of columns and rows with a

cell that has two transistors at each cell that has two transistors at each intersection as Control gate and Floating intersection as Control gate and Floating gate transistor.gate transistor.

• The principle of operation is based on The principle of operation is based on MOSFETs.MOSFETs.

Types of NAND FlashTypes of NAND Flash• Single Level Cell (SLC)Single Level Cell (SLC)• Multi Level Cell (MLC)Multi Level Cell (MLC)

SLC vs. MLCSLC vs. MLC

ITEM SLC MLC

Voltage 3.3V/1.8V 3.3V

Chip Size 0.12um 0.16um

Page Size/Block Size 2KB/128KB 512B/32KB or 2KB/256KB

Access Time(Max.) 25us 70us

Endurance 100K 10K

Cost per Bit more Comparatively less

Write Data Rate 8MB/s+ 1.5MB/s

SSD ElementsSSD ElementsSSD consists of basically three elements:SSD consists of basically three elements:• SSD Controller.SSD Controller.• SSD Flash.SSD Flash.• SSD Interface.SSD Interface.

SSD ControllerSSD Controller

• Flash controller includes the electronics Flash controller includes the electronics that bridge the Flash memory components that bridge the Flash memory components to the SSD input/output interfaces. to the SSD input/output interfaces.

• The controller is an embedded processor The controller is an embedded processor that executes firmware-level software. that executes firmware-level software.

SSD Controller Block DiagramSSD Controller Block Diagram• ProcessorProcessor• ECCECC• Flash ControllerFlash Controller• DRAM ControllerDRAM Controller• I/O InterfaceI/O Interface• Controller MemoryController Memory• Chip ConfigurationChip Configuration

SSD FlashSSD Flash• Solid State Flash memory is available using Solid State Flash memory is available using

NAND technology.NAND technology.•   NAND Flash components come in densities NAND Flash components come in densities

from 1Gb (gigabit) to 64Gb per chip.from 1Gb (gigabit) to 64Gb per chip.• NAND Flash components have structures NAND Flash components have structures

called pages and blocks.called pages and blocks.• There is an Error Correction Code (ECC) There is an Error Correction Code (ECC)

associated with each sector. associated with each sector. • NAND Flash has a limited rewrite endurance NAND Flash has a limited rewrite endurance

of about 1,000,000 times per block. of about 1,000,000 times per block. 

SSD InterfaceSSD Interface• Interface is used to connect the SSD with the Interface is used to connect the SSD with the

computer.computer.• Also, since SDDs are generally used in Also, since SDDs are generally used in

conjunction with magnetic disk drives, a conjunction with magnetic disk drives, a common mass storage bus interface is used common mass storage bus interface is used in most cases.in most cases.

• SSD are available with a variety of system SSD are available with a variety of system interfaces based primarily on the interfaces based primarily on the performance requirements:performance requirements: Serial ATASerial ATA Serial attached SCSI Serial attached SCSI 

Fiber Channel Fiber Channel  USBUSB

SSD Storage SchemeSSD Storage Scheme

• Groups of NAND flash cells are organized Groups of NAND flash cells are organized into pages and these pages are organized into pages and these pages are organized into blocks.into blocks.

• Read and write operations can be Read and write operations can be performed on pages, but erase operations performed on pages, but erase operations can only be performed at the block level.can only be performed at the block level.

• This means that when rewriting a page, This means that when rewriting a page, the entire block must be erased first. the entire block must be erased first.

• The SSD controller manages this processThe SSD controller manages this process..

SSD Around UsSSD Around Us

Mobile Media PlayersSolid-State Disks (SSD)

Thumb Disks Multimedia Memory Cards

Embedded Systems

Intel x25 SSD- An ExampleIntel x25 SSD- An Example

• Certified for 25 MB/s read speed and 70 Certified for 25 MB/s read speed and 70 MB/s write speed.MB/s write speed.

• MLS SSD standard.MLS SSD standard.• 10-channel memory controller.10-channel memory controller.• Each channel is “responsible” for two Each channel is “responsible” for two

memory chips.memory chips.• http://www.insidehw.com/Reviews/ http://www.insidehw.com/Reviews/

Storage/Intel-X25-M-SSD.htmlStorage/Intel-X25-M-SSD.html

SSD vs. HDDSSD vs. HDD

SSDSSD ApplicationsApplications• ServersServers• Desktop computersDesktop computers• LaptopsLaptops• Ultra booksUltra books• HD CamcordersHD Camcorders• Smart TVSmart TV• CCTV Digital Video Recorder (DVR)CCTV Digital Video Recorder (DVR)• Set-Top BoxesSet-Top Boxes• Gaming ConsolesGaming Consoles

Advantages High performance – significantly faster than a High performance – significantly faster than a

standard HDDstandard HDD Higher reliability – no moving parts, can withstand Higher reliability – no moving parts, can withstand

1500Gs operating shock1500Gs operating shock Lower power – Lesser power consumption ,cooler Lower power – Lesser power consumption ,cooler

operationoperation Silent operation – ideal for post production Silent operation – ideal for post production

environmentsenvironments Lighter weight – perfect for portable devicesLighter weight – perfect for portable devices Wider operating Temp. - 0c – 70c Wider operating Temp. - 0c – 70c

Disadvantages

• They are more expensive than traditional They are more expensive than traditional hard driveshard drives

• They currently offer less storage space than They currently offer less storage space than traditional hard drives.traditional hard drives.

• Slower Write Speed on low-end Slower Write Speed on low-end Models(MLC based types)Models(MLC based types)

Conclusion

• Faster Data AccessFaster Data Access• Less Power Usage Less Power Usage • Higher ReliabilityHigher Reliability• Latest high-end laptops and ultra books now Latest high-end laptops and ultra books now

comes with SSDcomes with SSD• In coming years SSD Will Replace Hard Disk In coming years SSD Will Replace Hard Disk

DrivesDrives

ReferencesReferences•http://en.wikipedia.org/wiki/Solid_state_driveshttp://en.wikipedia.org/wiki/Solid_state_drives•http://www.storagereview.com/http://www.storagereview.com/ssd_reference_guidessd_reference_guide•http://electronics.howstuffworks.com/flash-http://electronics.howstuffworks.com/flash-memory.htmmemory.htm•http://i.dell.com/sites/content/business/http://i.dell.com/sites/content/business/solutions/whitepapers/en/Documents/wp-solutions/whitepapers/en/Documents/wp-2009-SSD.pdf2009-SSD.pdf

Thank You.