LX5240 Datasheet, PDF (1/5 Pages) Microsemi Corporation – MULTIMODE, PLUG AND PLAY SCSI TERMINATOR

T H E I N F I N I T E P O W E R O F I N N O VAT I O N
L I N D O C #: 5240
UltraMAX^TM
LX5240
MULTIMODE, PLUG AND PLAY SCSI TERMINATOR
PR O D U C T I O N D ATA S H E E T
DESCRIPTION
The LX5240 is a multimode SCSI terminator with
plug-and-play capability that conforms to the
SCSI Parallel Interconnect-2 (SPI-2) specification
developed by the T10 standards committee for
low voltage differential (LVD) termination, while
providing backwards compatibility to the SCSI,
SCSI-2, and SPI single-ended specifications.
Multimode compatibility permits the use of
legacy devices on the bus without hardware
alterations. Automatic mode selection is
achieved through voltage detection on the
diffsense line.
The LX5240 utilizes Linfinity’s UltraMAX tech-
nology which delivers the ultimate in SCSI bus
performance while saving component cost and
board area. Elimination of the external capaci-
tors also mitigates the need for a lengthy ca-
pacitor selection process. The individual high
bandwidth drivers also maximize channel sepa-
ration and reduce channel to channel noise and
cross talk. The high bandwidth architecture
insures ULTRA2 performance while providing
a clear migration path to ULTRA3 and beyond.
When the LX5240 is enabled, the differential
sense (DIFFSENSE) pin supplies a voltage be-
tween 1.2V and 1.4V. In application, this pin
is tied to the DIFFSENSE input of the corre-
sponding LVD transceivers. This action enables
the LVD transceiver function. DIFFSENSE is
capable of supplying a maximum of 15mA.
Tying the DIFFSENSE pin high places the
LX5240 in a HI Z state indicating the presence
of an HVD device. Tying the pin low places
the part in a single-ended mode while also
signaling the multimode transceiver to operate
in a single-ended mode.
The LX5240 supports full Plug and Play
functionality with the DISCONNECT A and B
pins. These logic compatible pins place the
device in operational or sleep modes. During
sleep mode, power dissipation is reduced to
a meager 15µA while also placing all outputs
in a HI Z state. Also during sleep mode, the
DIFFSENSE function is disabled and is placed
in a HI Z state.
Another key feature of the LX5240 is the
master / slave function. Driving this pin high
or floating the pin enables the 1.3V DIFFSENSE
reference. Driving the pin low disables the on
board DIFFSENSE reference and enables use
of an external master reference device.
NOTE: For current data & package dimensions, visit our web site: http://www.linfinity.com.
B US V OLTAGE
PRODUCT HIGHLIGHT
KEY FEATURES
s Auto-Selectable LVD Or
Single-Ended Termination
s 3.0pF Maximum Disabled Output
Capacitance
s Fast Response, No External Capacitors
Required
s Compatible With Active Negation
Drivers
s 15µA Supply Current In Disconnect
Mode
s Logic Command Disconnects All
Termination Lines
s Diffsense Line Driver
s Ground Driver Integrated For Single-
Ended Operation
s Current Limit And Thermal Protection
s Hot-Swap Compatible
(Single-Ended)
s Compatible With SCSI 1, 2, 3, Fast-20,
And The Pending SPI-2 LVD
s Plug And Play Compatible
s See LX5245/5246, LVD Termination Only
V _OD
V_OD = V_(-) - V₍₊₎, Logic = 0
V₍₊₎
NEGATED
100mV
0V
V_(-)
-100mV
LX5240
LX5240
PACKAGE ORDER INFO
T_A (°C)
DB
Plastic SSOP
36-pin
PW
Plastic
24-pin
TSSOP
0 to 70
LX5240CDB
LX5240CPW
Note: All surface-mount packages are available in Tape & Reel.
Append the letter "T" to part number. (i.e. LX5240CDBT)
LINFINITY MICROELECTRONICS INC.
Copyright © 1999
Rev. 1.1 10/00
11861 WESTERN AVENUE, GARDEN GROVE, CA. 92841, 714-898-8121, FAX: [phone]
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