Microsemi Corporation LX5219CPW, LX5219CDW Datasheet

LIN DOC #:

5219

UltraMAX

ULTRA 9-CHANNEL SCSI TERMINATOR

THE INFINITE POWER OF INNOVATION

DESCRIPTION KEY FEATURES

The LX5219 SCSI terminator is part of Linfinity's
UltraMAX family of high-performance, adaptive, non­linear mode SCSI products, which are designed to
deliver true UltraSCSI performance in SCSI applica­tions. The low voltage BiCMOS architecture em­ployed in its 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. It is approved for use with SCSI­1, -2, -3, UltraSCSI and beyond — providing the
highest performance alternative available today.

Another key improvement offered by the LX5219
lies in its 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 con-

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

trolled by the peripheral or host designer and, when
problems occur, they are the first to be made aware
of the problem. The LX5219 architecture is much
more tolerant of marginal system integrations.

Recognizing the needs of portable and
configurable peripherals, the LX5219 has an active
low 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 sleep­mode 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 compo­nents which, often times results in field returns due
to mishandling.

Reduced component counts is also inherent in
the LX5219 architecture. Traditional termination
techniques require large stabilization and transient
protection capacitors of up to 20µF in value and
size. The LX5219 architecture does not require these
components, allowing all the cost savings associated
with inventory, board space, assembly, reliability,
and component costs.

P RODUCTION DATA SHEET

TM

LX5219

■ ULTRA-FAST RESPONSE FOR FAST-20

SCSI APPLICATIONS

■ HOT SWAP COMPATIBLE

■ 35MHz CHANNEL BANDWIDTH

■ 3.5V OPERATION

■ LESS THAN 3pF OUTPUT CAPACITANCE

■ SLEEP-MODE CURRENT LESS THAN

275µA

■ THERMALLY SELF LIMITING

NO EXTERNAL COMPENSATION

■

CAPACITORS

■ IMPLEMENTS 8-BIT OR 16-BIT (

APPLICATIONS

■ COMPATIBLE WITH ACTIVE NEGATION

DRIVERS (60mA / CHANNEL)

■ COMPATIBLE WITH PASSIVE AND

ACTIVE TERMINATIONS

■ APPROVED FOR USE WITH SCSI 1, 2, 3

AND ULTRASCSI

■ CONSULT FACTORY FOR APPLICATION

TEST REPORT

■ EVALUATION BOARD AVAILABLE

WIDE

)

PRODUCT HIGHLIGHT

DRIVING WAVEFORM - 20MHZRECEIVING WAVEFORM - 20MHZ

Receiver

1 Meter, AWG 28

LX5219 LX5219

LX5268 LX5268

PACKAGE ORDER INFORMATION

T

(°C)

J

Plastic SOWB

DW PW

16-pin

0 to 70 LX5219CDW LX5219CPW

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

Append the letter "T" to part number. (i.e. LX5219CDWT)

Driver

Plastic TSSOP
20-pin

NOTE:

For An In-Depth

Discussion On Applying

SCSI, Request Linfinity

Application Note:

"Understanding The

Single-Ended SCSI Bus"

Copyright © 1998
Rev. 1.8 3/98

L INFINITY MICROELECTRONICS INC.

11861 WESTERN AVENUE, GARDEN GROVE, CA. 92841, 714-898-8121, FAX: [phone]

1

PRODUCT DATABOOK 1996/1997

LX5219

ULTRA 9-CHANNEL SCSI TERMINATOR

RODUCTION DATA SHEET

P

ABSOLUTE MAXIMUM RATINGS (Note 1)

Continuous Termination Voltage .......................................................................... 10V

Continuous Output Voltage Range .............................................................. 0 to 5.5V

Continuous Disable Voltage Range ............................................................. 0 to 5.5V

Operating Junction Temperature ........................................................... 0°C to 125°C

Storage Temperature Range ............................................................. -65°C to +150°C

Solder Temperature (Soldering, 10 seconds) ................................................... 300°C

Note 1. Exceeding these ratings could cause damage to the device.

THERMAL DATA

DW PACKAGE:

D

x θ

θθ

θ

θθ

JA

θθ

θ

θθ

JA

).

JA

THERMAL RESISTANCE-JUNCTION TO AMBIENT,

PW PACKAGE:

THERMAL RESISTANCE-JUNCTION TO AMBIENT,

Junction Temperature Calculation: TJ = TA + (P

numbers are guidelines for the thermal performance of the device/pc-board system.

The θ

JA

All of the above assume no ambient airflow.

95°C/W

144°C/W

UltraMAX

PACKAGE PIN OUTS

TERM POWER

GND

TERM POWER

N.C.
N.C.

D0
D1
D2
D3
D4

N.C.

GND

1 16

215

N.C.

314

D0

413

D1

512

D2

611

D3

710

D4

89

DW PACKAGE

(Top View)

219

318

417

516

615

714

813

912
10 11

20

TERM POWER
N.C.
DISABLE
D8
D7
D6
D5
GND

TERM POWER
DISABLE
N.C.
D8
D7
N.C.
D6
D5
N.C.
GND

PW PACKAGE

(Top View)

2

Copyright © 1998

Rev. 1.8 3/98

PRODUCT DATABOOK 1996/1997

UltraMAX

LX5219

ULTRA 9-CHANNEL SCSI TERMINATOR

P RODUCTION DATA SHEET

RECOMMENDED OPERATING CONDITIONS (Note 2)

Parameter

Termination Voltage V
High Level Disable Input Voltage V

Low Level Disable Input Voltage V

Operating Virtual Junction Temperature Range

LX5219C

Note 2. Range over which the device is functional.

Symbol

TERM

IH

IL

ELECTRICAL CHARACTERISTICS

Term Power = 4.75V unless otherwise specified. Unless otherwise specified, these specifications apply at the recommended operating ambient tempera­ture of T

= 25°C. Low duty cycle pulse testing techniques are used which maintains junction and case temperatures equal to the ambient temperature.

A

Parameter

Output High Voltage V

TermPwr Supply Current I

Output Current I
Disable Input Current Disable Pin = 4.75V

Output Leakage Current Disable Pin = < 0.8V, V

Capacitance in Disabled Mode C
Channel Bandwidth BW
Termination Sink Current, per Channel I

Symbol

OUT

CC

OUTVOUT

OUTVOUT

SINKVOUT

Test Conditions Units

All data lines = open
All data lines = 0.5V
Disable Pin < 0.8V

= 0.5V

Disable Pin = 0V

= 0V, frequency = 1MHz

= 4V

= 0.5V

O

Recommended Operating Conditions

Min. Typ. Max.

3.5 5.5 V
2V

0 0.8 V

0 125 °C

TERM

LX5219

Min. Typ. Max.

2.65 2.85 V

69mA
215 225 mA

375 µA

-21 -23 -24 mA
10 nA

-90 µA
10 nA

3pF
35 MHz
60 mA

Units

V

Copyright © 1998
Rev. 1.8 3/98

3

PRODUCT DATABOOK 1996/1997

T

LX5219

DISABLE

PIN

1.4V

TERM POWER

THERMAL
LIMITING

ULTRA 9-CHANNEL SCSI TERMINATOR

RODUCTION DATA SHEET

P

BLOCK DIAGRAM

CURRENT

BIASING

CIRCUIT

CIRCUIT

24mA CURRENT

LIMITING CIRCUIT

2.85V

UltraMAX

DATA OUTPU
PIN DB(0)

1 OF 9 CHANNELS

FUNCTIONAL DESCRIPTION

Cable transmission theory suggests to optimize signal speed
and quality, the termination should act both as an ideal voltage
reference when the line is released (deasserted) and as an
ideal current source when the line is active (asserted).
Common active terminators, which consist of Linear Regulators
in series with resistors (typically

110Ω), are a compromise. As the

line voltage increases, the amount
of current decreases linearly by the
equation V = I * R. The LX5219,
with its unique new architecture
applies the maximum amount of
current regardless of line voltage
until the termination high thresh­old (2.85V) is reached.

Acting as a near ideal line terminator, the LX5219 closely
reproduces the optimum case when the device is enabled.
To enable the device the Disable Pin must be pulled logic
High or left Open. During this mode of operation, quiescent
current is 6mA and the device will respond to line demands

POWER UP / POWER DOWN FUNCTION TABLE

Disable

(LX5219) Current

H Enabled 6mA

L HI Z 275µA

Open Enabled 6mA

by delivering 24mA on assertion and by imposing 2.85V on
deassertion. In order to disable the device, the Disable pin
must be driven logic Low. This mode of operation places
the device in a sleep state where a meager 275µA of quiescent
current is consumed. Additionally, all outputs are in a Hi-Z

(impedance) state. Sleep mode can
be used for power conservation or

Outputs

LX5219 has been optimized to have only 3pF of capacitance
per output in the sleep state.

An additional feature of the LX5219 is its compatibility with
active negation drivers. The device handles up to 60mA of
sink current for drivers which exceed the 2.85V output high.

Quiescent

to completely eliminate the termi­nator from the SCSI chain. In the
second case, termination node ca­pacitance is important to consider.
The terminator will appear as a
parasitic distributed capacitance on

the line, which can detract from bus
performance. For this reason, the

4

Copyright © 1998

Rev. 1.8 3/98