10 Things You Need To Know About Designing Enterprise SSD

10/2016

Simon Huang

Email:simonhuang1688@gmail.com

1. Inside of SSD2. SSD Interface3. NAND Flash Interface4. Form Factor5. NAND Type and Endurance6. NAND Geometry 7. NAND Package8. NAND Flash Controller Maker 9. SSD Buffer 10. NAND Vendors11. Power Loss Protection

Inside of SSD

DDR3 Cache

NAND, BGA(Storage Media)

Controller

SAS Interface (two ports)

PCBA

SAS Power

• SATA III• SAS 12Gb• PCI-e NVMe ( G2, G3, G4 )

SSD Interface

• ONFI 2.0, 3.0, 4.0• Toggle 1.0, 2.0, 3.0

NAND Flash Interface

Form Factor

• AIC (FHFL, FHHL, HHHL)• M.2 (2280, 22110) • 2.5 in x 7 mm (U.2)• 2.5 in x 15 mm (U.2)

NAND Type and Endurance

Type P/E

Cycle Cost

Random Write performance

comparing HDD

SLC 100K High 5X

eMLC 30K Middle 3X

MLC 10K Low 2X

TLC 1K Very Low 1X

NAND Geometry

• 42nm -> 32nm -> 25nm/24nm -> 20nm/19nm -> 16nm/15nm -> 12nm -> ? nm

NAND Package

• TSOP (48)• BGA (132, 152, 272)• CE ( 2, 4, 8, 16)• Channel ( 2, 4, 8)

NAND Flash Controller Maker

SSD Buffer• DDR3 * 2/4• DDR4 * 2/4

SSD

CPU

HostInterfaceController

BufferController

FlashController

Buffer

DRAM

ECC

FlashMemory

FlashMemory

ControllerPLP

Circuit Metadata 0 1 2 3

Host

DRAM

NAND Vendors

Power Loss Protection

Without Tantalum Capacitor/Supercaps: - Metadata will be secured and SSD canreboot again after system power recover.

- Level one PLP

With Tantalum Capacitor/Supercaps: - MetaData and DRAM buffer data will be secured and SSD can reboot after system power recover.

- Level two PLP