T
H E
™
LX5241/5242/5243
I
N F I N I T E
P
O W E R
O F
I
N N O V A T I O N
The LX5241/42/43 is a multimode SCSI
terminator that is compatible with to the SCSI
SPI02 (Ultra2 SCSI), SCSI SPI-3 (Ultra3 SCSI or
Ultra160 SCSI), and pending SCSI SPI-4
(Ultra320) specifications 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
LX5241/42/43
utilizes
Linfinity’s
UltraMAX technology which delivers the ultimate
in SCSI bus performance while saving component
cost and board area. Elimination of the external
capacitors also mitigates the need for a lengthy
capacitor selection process. The individual high
bandwidth drivers also maximize channel
separation 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 LX5241/42/43 is enabled, the
differential sense (DIFFSENSE) pin supplies a
voltage between 1.2V and 1.4V. In application
this pin is tied to the DIFFSENSE input of the
corresponding 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 LX5241/42/43 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.
Recognizing the needs of portable and
configurable peripherals, the LX5241/42/43 have
a TTL compatible sleep/disable mode. During
this sleep/disable mode, power dissipation is
reduced to a meager 15uA while also placing all
outputs in a HI Z state. Also during sleep/disable
mode, the DIFFSENSE function is disabled and is
placed in a HI Z state.
Another key feature of the LX5241/42/43 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.
Auto-Selectable LVD or Single-
Ended Termination
3.0pF Maximum Disabled Output
Capacitance
Fast Response, No External
Capacitors Required
Compatible with Active Negation
Drivers
15µA Supply Current in
Disconnect Mode
Logic Command Disconnects All
Termination Lines
Diffsense Line Driver
Ground Driver Integrated for
Single-Ended Operation
Current Limit and Thermal
Protection
Hot-Swap Compatible (Single-
Ended)
Ultra160 compliant
See LX5245/5246 for LVD
Termination Only
Pin Compatible With DS2119
and UCC5630
IMPORTANT:
For the most current data, consult
MICROSEMI
’s website:
http://www.microsemi.com
B
US
V
OLTAGE
6
V
(+)
V
CM
V
OD
V
OD
= V
(-)
- V
(+)
, Logic = 0
NEGATED
100mV
0V
-100mV
V
(-)
-
-
LX 5241
+
+
LX 5241
T
A
(°C)
0 to 70
DB
Plastic TSSOP
36-Pin
LX5241CDBK
LX5242CDBK
PW
Plastic TSSOP
24-Pin
LX5241CPWK
LX5242CPWK
PW
Plastic TSSOP
28-Pin
LX5243CPW
-
Note: Available in Tape & Reel.
Append the letter “T” to the part number. (i.e. LX5241CDBT)
Copyright
©
2000
Rev. 1.4,2000-11-28
L
IN
F
INITY
M
ICROELECTRONICS
I
NC
.
11861 W
ESTERN
A
VENUE
, G
ARDEN
G
ROVE
, CA. 92841, 714-898-8121, F
AX
: 714-893-2570
1
MICROSEMI [ MICROSEMI CORPORATION ]
