LX5111A

The LX5111A/5112A SCSI terminators are part of Linfinity's UltraMAX family of high-performance, adaptive, non-linear mode SCSI products, which are designed to deliver true UltraSCSI performance in SCSI applications. The low voltage BiCMOS architecture employed in their design offers superior performance to older linear passive and active techniques. Linfinity's UltraMAX architecture employs high-speed adaptive elements for each channel, thereby providing the fastest response possible - typically 35MHz, which is 100 times faster than the older linear regulator/terminator approach used by other manufacturers. Products using this older linear regulator approach have bandwidths which are dominated by the output capacitor and which are limited to 500KHz (see further discussion in the Functional Description section). The UltraMAX architecture also eliminates the output compensation capacitor typical in earlier terminator designs. Each is approved for use with SCSI-1, -2, -3, UltraSCSI and beyond - providing the highest performance alternative available today.

Another key improvement offered by the LX5111A/12A lies in their ability to insure reliable, error-free communications even in systems which do not adhere to recommended SCSI hardware design guidelines, such as the use of improper cable lengths and impedances.

Frequently, this situation is not controlled by the peripheral or host designer and, when problems occur, they are the first to be made aware of the problem. The LX5111A/12A architecture is much more tolerant of marginal system integrations. Recognizing the needs of portable and configurable peripherals, the LX5111A/12A have a TTL compatible sleep/disable mode.

Quiescent current is typically less than 275µA in this mode, while the output capacitance is also less than 3pF. The obvious advantage of extended battery life for portable systems is inherent in the product's sleep-mode feature. Additionally, the disable function permits factory-floor or production-line configurability, reducing inventory and productline diversity costs. Field configurability can also be accomplished without physically removing components which, often times results in field returns due to mishandling.

Reduced component counts is also inherent in the LX5111A/12A's architecture. Traditional termination techniques require large stabilization and transient protection capacitors of up to 20µF in value and size. The LX5111A/12A architecture does not require these components, allowing all the cost savings associated with inventory, board space, assembly, reliability, and component costs.