User:Ronseese/Sandbox

Solid State Disk Adapter

A Solid-State Drive Adapter is the combination of a host adapter interface with a flash memory based Solid-state drive, implemented as a single card. This card when plugged into the target system, provides a solid state solution for what would typically be the hard disk that holds all user and system data. By using standard off the shelf SSD memory, the adapter integrates all components into a single card that plugs directly into the target system. These systems extend well beyond desktop computers, and also include media servers and embedded computing devices. Such an adapter is used where typical rotating media (a standard disk drive) can not be tolerated because of its lack of robustness (need to fix this).

Cables have been a major source of system failure over the years. By combining the two components, the SSD memory with the host interface, all cabling is eliminated, thus providing a more robust solution.

One of the benefits of the SSD technology is that the typical disk drive, which uses a rotating platter and moving components , is replaced with a completely solid state device. In this context, SSD devices are not subject to the effects of extreme vibration and shock conditions that a typical disk drive does. By combining the media with the host bus adapter, connecting cabling is eliminated which is another source of system failure.

Flash memory, which is typically used in SSD designs, has a limitation of the number of writes that can be performed to the flash IC. This limitation is characterized as endurance and is specified in each manufacturer's devices. This specification ranges from manufacture to manufacture, but is typically in the millions of writes. RAID technology allows for multiple devices to be accessed simultaneously where the data is spread across the devices. This concept improves upon the write endurance specification by allowing more data to be written to the device.

These concepts are demonstrated in Lauron's products, one of such is the LT-PCI-CF. This PCI (Peripheral Component Interconnect) adapter uses a RAID bridge IC which is the host bus adapter. The RAID interface can be configured as a 4 port data path. Doing such improves performance since data is transfered on all 4 ports simultaneously. It also offers the improved endurance ratings as less write cycles are needed for the same amount of data written to the device. CompactFlash is used for the media, which is consistently less expensive than SSD modules. CompactFlash endurance specifications range, but industrial versions offers the endurance of 2,000,000 write cycles.