Technology

HLNAND’s patented daisy-ring architecture delivers the SSD industry’s most advanced capabilities for mass storage applications.

MOSAID's HLNAND™ Solid State Drive (SSD) Prototype

Introduction


MOSAID’s innovative HyperLink NAND (HLNAND™) architecture and interface combines our HyperLink memory technology with industry standard NAND Flash cell technology. HLNAND delivers sustained I/O bandwidths an order of magnitude greater than conventional Flash by utilizing a point-to-point ring topology that achieves an extremely high level of signal integrity and significantly reduced loading.

MOSAID’s 128GB HLNAND SSD prototype demonstrates that 213MBps read performance and 130MBps write performance is achievable on a single channel of HLNAND Flash memory. The SSD is a fully functional, Serial ATA2 (SATA2) compatible prototype incorporating a Field Programmable Gate Array (FPGA)-based controller and MOSAID’s HLNAND modules, built in the 3.5 inch form factor. The HLNAND SSD prototype uses two 64GB HLDIMM modules (eight multi-chip packages (MCPs) per module, 16 MCPs in total) arranged on a single channel. MOSAID provided the HLDIMM modules, with development partner INDILINX building the controller and system board.

Features

  • 128GB on a single Flash channel
  • 2 x 64GB HLNAND Flash modules, SODIMM form factor
  • 16 MCP, 64 independent banks
  • DDR266 HyperLink interface
  • Dynamic page size: addressable from 512B – 4KB
  • Concurrent Read & Write capability
  • Controller developed by INDILINX
  • Virtex5 - 75MHz Core Frequency
  • SATA 2 host interface
  • NCQ support
  • Single HLNAND Channel @ 150MTs
  • 64MB External SDRAM

Performance

  • @ 75MHz (FPGA limit): 120MB/s/ch. seq. read, 73MB/s/ch. seq. write
  • @ 133MHz, translates to: 212MB/s/ch. seq. read, 130MB/s/ch. seq. write
  • 8 Ch. HL SSD capable of 1.7GB/s seq. read

Further tuning will bring rates close to the 266MB/s/ch. Maximum, or 2.1GBps/ch.


Single Channel Performance






Architecture


A key factor limiting the throughput of conventional NAND Flash is its parallel bus topology, with heavy loading and poor signal integrity causing a reduced data rate. In turn, SSDs using conventional Flash devices suffer in performance and require a large degree of parallelism to provide the required capacity.


The HLNAND SSD prototype utilizes MOSAID’s HyperLink interface, composed of a synchronous, DDR, point-to-point ring with superior signal integrity and minimized bus loading. The result is an interface that operates at 133MHz, or DDR266, and is highly scalable. Only with HLNAND is it possible populate up to 255 Flash devices on a single channel without suffering any loss in data rate, which vastly simplifies the job of developing high-capacity, high-speed SSDs.



The HLNAND SSD prototype demonstrates that it is possible to achieve performance results with a single channel of HLNAND Flash that would require up to 10 channels of conventional Flash to achieve. An SSD built using an ASIC controller running at full speed, or 133MHz, and having only three channels of HLNAND, would achieve close to 800MBps data rate, more than enough to saturate SATA3, at 6Gbps. Building the same SSD with eight channels would achieve close to 2.1GBps data rate, more than enough to saturate four lanes of PCIe 2.x.


For more information, contact:
Roland Schuetz
Director, Applications & Business Initiatives
Memory Solutions
613-599-9539 x1463
schuetz@mosaid.com