
TM
UltraMAX
LX5115A
ULTRA 9-CHANNEL SCSI TERMINATOR
T HE I NFINITE P OWER OF I NNOVATION
P RODUCTION DATA SHEET
DESCRIPTION KEY FEATURES
The LX5115A 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 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. 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
LX5115A lies in its ability to insure reliable, errorfree communications even in systems which do
not adhere to recommended SCSI hardware design
guidelines, such as the use of improper cable
NOTE: For current data & package dimensions, visit our web site: http://www.linfinity.com.
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 LX5115A
architecture is much more tolerant of marginal
system integrations.
Recognizing the needs of portable and
configurable peripherals, the LX5115A has a TTL
compatible sleep/disable mode. Quiescent
current is typically 200µA 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 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 LX5115A architecture. Traditional termination
techniques require large stabilization and transient
protection capacitors of up to 20µF in value and
size. The LX5115A architecture does not require
these components, allowing all the cost savings
associated with inventory, board space, assembly,
reliability, and component costs.
■ Ultra-Fast Response For Fast-20 SCSI
Applications
■ 35MHz Channel Bandwidth
■ Less Than 3pF Output Capacitance
■ Sleep-Mode Current Of 200µA
■ NO External Compensation Capacitors
■ Implements 8-Bit Or 16-Bit (
Applications
■ Compatible With Active Negation
Drivers
■ Compatible With Passive And Active
Terminations
■ Approved For Use With SCSI 1, 2, 3
And Ultra SCSI
■ Hot Swap Compatible
■ Pin-For-Pin Compatible With
DS21S07A / 2105
Wide
)
PRODUCT HIGHLIGHT
DRIVING WAVEFORM - 20MHZRECEIVING WAVEFORM - 20MHZ
Receiver
1 Meter, AWG 28
LX5115A
LX5268 LX5268
PACKAGE ORDER INFORMATION
T
(°C)
J
Plastic SOIC
D
16-pin
Plastic SOWB
DW
16-pin
0 to 70 LX5115ACD LX5115ACDW LX5115ACPWP
Note: All surface-mount packages are available in Tape & Reel.
Append the letter "T" to part number. (i.e. LX5115ACDWT)
Driver
LX5115A
PWP
Plastic TSSOP
20-pin, Power
NOTE:
For An In-Depth
Discussion On Applying
SCSI, Request Linfinity
Application Note:
"Understanding The Single-
Ended SCSI Bus"
Copyright © 2000
Rev. 1.0 4/00
L INF INITY MICROELECTRONICS INC.
11861 WESTERN AVENUE, GARDEN GROVE, CA. 92841, 714-898-8121, FAX: 714-893-2570
1

PRODUCT DATABOOK 1996/1997
LX5115A
ULTRA 9-CHANNEL SCSI TERMINATOR
P RODUCTION DATA SHEET
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
D PACKAGE:
THERMAL RESISTANCE-JUNCTION TO AMBIENT,
DW PACKAGE:
THERMAL RESISTANCE-JUNCTION TO AMBIENT,
PWP PACKAGE:
THERMAL RESISTANCE-JUNCTION TO AMBIENT,
Junction Temperature Calculation: TJ = TA + (PD x θJA).
The θJA numbers are guidelines for the thermal performance of the device/pc-board system.
All of the above assume no ambient airflow.
θθ
θ
θθ
JA
θθ
θ
θθ
JA
θθ
θ
θθ
JA
120°C/W
95°C/W
139°C/W
UltraMAX
PACKAGE PIN OUTS
TERM POWER
N.C.
GND
TERM POWER
N.C.
GND
D0
D1
D2
D3
D4
D PACKAGE
(Top View)
1 16
215
D0
314
D1
413
D2
512
D3
611
D4
710
89
DW PACKAGE
(Top View)
215
314
413
512
611
710
89
DISABLE
16
N.C.
D8
D7
D6
D5
N.C.
N.C.
DISABLE
N.C.
N.C.
D8
D7
D6
D5
N.C.
TERM POWER
HEATSINK/GND
HEATSINK/GND
N.C.
GND
219
318
D0
417
D1
516
D2
615
D3
714
D4
813
912
10 11
PWP PACKAGE
(Top View)
20
DISABLE
N.C.
HEATSINK/GND
N.C.
D8
D7
D6
D5
HEATSINK/GND
N.C.
2
Copyright © 2000
Rev. 1.0 4/00

PRODUCT DATABOOK 1996/1997
UltraMAX
LX5115A
ULTRA 9-CHANNEL SCSI TERMINATOR
P RODUCTION DATA SHEET
RECOMMENDED OPERATING CONDITIONS (Note 2)
Parameter
Termination Voltage V
High Level Enable Input Voltage V
Low Level Disable Input Voltage V
Operating Virtual Junction Temperature Range
LX5115AC
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 TA = 25°C. Low duty cycle pulse testing techniques are used which maintains junction and case temperatures equal to the ambient temperature.
Parameter
Output High Voltage V
Term Power Supply Current I
Output Current I
Disable Input Current I
Output Leakage Current I
Capacitance in Disabled Mode C
Channel Bandwidth BW
Termination Sink Current, per Channel I
Symbol
OUT
CC
OUTVOUT
IN
OL
OUTVOUT
SINKVOUT
Test Conditions Units
Term Power = 4.75V
Term Power = 3.0V
All data lines = open
All data lines = 0.5V
Disable Pin < 0.8V
= 0.5V, Term Power = 4.75V
V
= 0.5V, Term Power = 3.0V
OUT
Disable Pin = 4.75V
Disable Pin = 0V
Disable Pin = < 0.8V, VO = 0.5V
= 0V, frequency = 1MHz
= 4V
Recommended Operating Conditions
Min. Typ. Max.
3.0 5.5 V
2.5 V
00.8V
0 125 °C
TERM
LX5115A
Min. Typ. Max.
2.65 2.85 V
2.1 2.2 V
5.5 9 mA
210 225 mA
200 µA
-21 -23 -24 mA
-17 -18 mA
80 nA
-12 µA
20 nA
3pF
35 MHz
711 mA
Units
V
Copyright © 2000
Rev. 1.0 4/00
3

PRODUCT DATABOOK 1996/1997
LX5115A
DISABLE
PIN
2.0V
TERM POWER
ULTRA 9-CHANNEL SCSI TERMINATOR
P RODUCTION DATA SHEET
BLOCK DIAGRAM
CURRENT
BIASING
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
LX5115A, with its unique new architecture applies the maximum amount
of current regardless of line voltage
POWER UP / POWER DOWN FUNCTION TABLE
Disable
LX5115A Current
H Enabled 5.5mA
L HI Z 200µA
Open Enabled 5.5mA
Outputs
until the termination high threshold
(2.85V) is reached.
Acting as a near ideal line terminator, the LX5115A 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 5.5mA and the device will respond to line demands
PRODUCTION DATA - Information contained in this document is proprietary to LinFinity, and is current as of publication date. This document
may not be modified in any way without the express written consent of LinFinity. Product processing does not necessarily include testing of
all parameters. Linfinity reserves the right to change the configuration and performance of the product and to discontinue product at any time.
UltraMAX is a trademark of Linfinity Microelectronics Inc.
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 200µA of quiescent
current is consumed. Additionally, all
outputs are in a Hi-Z (impedance)
state. Sleep mode can be used for
Quiescent
power conservation or 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
LX5115A has been optimized to have only 3pF of capacitance
per output in the sleep state.
An additional feature of the LX5115A is its compatibility with
active negation drivers. The device handles up to 7mA of sink
current for drivers which exceed the 2.85V output high.
4
Copyright © 2000
Rev. 1.0 4/00