鈩?/div>
input pull-down resistors
s
Available in 16-pin SOIC package
PRELIMINARY
SY10EL1189
DESCRIPTION
The SY10EL1189 is a differential receiver, differential
transmitter specifically designed to drive coaxial cables.
It incorporates the output cable driver capability of the
SY10EL89 Coaxial Cable Driver with additional circuitry
to multiplex the output cable drive source between the
cable receiver or the local transmitter inputs. The
multiplexer control circuitry is TTL compatible for ease of
operation.
The SY10EL1189 is useful as a bypass element for
Fibre Channel-Arbitrated Loop (FC-AL) or Serial Storage
Architecture (SSA) applications, to create loop style
interconnects with fault tolerant, active switches at each
device node. This device is particularly useful for back
panel applications where small size is desirable.
The EL89 style drive circuitry produces swings twice
as large as a standard PECL output. When driving a
coaxial cable, proper termination is required at both ends
of the line to minimize reflections. The 1.6V output swings
allow for proper termination at both ends of the cable.
Because of the larger output swings, the QT, QT outputs
are terminated into the thevenin equivalent of 50鈩?to
V
CC
-3.0V instead of 50鈩?to V
CC
-2.0V.
LOGIC DIAGRAM
From Input Cable
(ECL Levels)
Local
Receive Data
(ECL Levels)
QR
QR
DR
DR
V
BB
1
Local
Transmit Data
(ECL Levels)
DT
DT
0
QT
To Output Cable
(Enhanced Swing)
SEL (TTL)
QT
PIN NAMES
Pin
DR/DR
Function
Differential Input from Receive Cable
Buffered Differential Output from Receive Cable
Differential Input to Transmit Cable
Buffered Differential Output to Transmit Cable
Multiplexer Control Signal (TTL)
Postive Power Supply
Ground
Reference Voltage Output
PIN CONFIGURATION
QR/QR
DT/DT
QT/QT
QR
QR
V
CC
NC
V
CC
QT
QT
V
CC
1
2
3
4
5
6
7
8
16
15
14
13
12
11
10
9
V
CC
DR
DR
GND
V
BB
DT
DT
SEL
SEL
V
CC
GND
V
BB
Top View
SOIC
TRUTH TABLE
SEL
L
H
DR
鉃?/div>
QT
DT
鉃?/div>
QT
Function
Rev.: C
Amendment: /2
1
Issue Date: January 2000
1
2
3
4
