OF

LX5218

DESCRIPTION

KEY FEA TURES

s SCSI PLUG AND PLAY, DUAL LOW

DISCONNECT, LOGIC LOW COMMAND

DISCONNECTS ALL TERMINATION LINES

s HOT SWAP COMPATIBLE

s ULTRA-FAST RESPONSE FOR FAST-20

SCSI APPLICATIONS

s 35MHz CHANNEL BANDWIDTH

s 3.5V OPERATION

s LESS THAN 3pF OUTPUT CAPACITANCE

s DISABLE-MODE CURRENT LESS THAN

275µA

s THERMALLY SELF LIMITING

s NO EXTERNAL COMPENSATION

CAPACITORS

s IMPLEMENTS 8-BIT OR 16-BIT (WIDE)

APPLICATIONS

s COMPATIBLE WITH ACTIVE NEGATION

DRIVERS (60mA / CHANNEL)

s COMPATIBLE WITH PASSIVE AND

ACTIVE TERMINATIONS

s APPROVED FOR USE WITH SCSI-1, -2, -3

AND ULTRASCSI

s CONSULT FACTORY FOR APPLICATION

TEST REPORT

0 to 70

LX5218CDW

LX5218CPW

P ACKAGE ORDER INFORMA TION

T

Note: All surface-mount packages are available in Tape & Reel.

Append the letter "T" to part number. (i.e. LX5218CDWT)

Plastic SOWB

16-pin

DW

20-pin

Receiver

LX5218

LX5218

LX5268

LX5268

1 Meter, AWG 28

Driver

PRODUCT HIGHLIGHT

The LX5218 SCSI terminator is 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 applica-

tions.

The low voltage BiCMOS architecture em-

ployed 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 regu-

lator/terminator approach used by other manufactur-

ers. Products using this older linear regulator ap-

proach 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. It 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 LX5218

lies in its ability to insure reliable, error free com-

munications 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 con-

trolled by the peripheral or host designer and, when

problems occur, they are the first to be made aware

of the problem. The LX5218 architecture is much

more tolerant of marginal system integrations.

The LX5218 has two disconnect pins for SCSI Plug

and Play (PnP) applications. Quiescent current is

typically less than (275µA) in disable 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 product-line

diversity costs.

Field configurability can also be

accomplished without physically removing compo-

nents which, often times results in field returns due

to mishandling.

Reduced component counts is also inherent in

the LX5218 architecture.

Traditional termination

techniques require large stabilization and transient

protection capacitors of up to 20µF in value and

size. The LX5218 architecture does not require these

components, allowing all the cost savings associated

with inventory, board space, assembly, reliability,

and component costs.

UltraMAX

TM

NOTE:

For An In-Depth

Discussion On Applying

SCSI, Request Linfinity

Application Note:

"Understanding The

Single-Ended SCSI Bus"

Copyright © 1997

Rev. 1.7

12/97

1

IMPORTANT: For the most current data, consult LinFinity's web site: http://www.linfinity.com.