13
LTC1334
Figure 18. Typical Cable Extension for RS232/EIA562 Interface
U
S
A
O
PP
L
IC
AT
I
WU
U
I FOR ATIO
RS422
RS232/EIA562
LTC1334 • F18
100Ω
100Ω
13
11
9
19 24
232217
8
DR OUT
RX IN
5V
4
5
6
7
LTC1334
RS232/EIA562
22
11
13
17
5V
9
19
24
23
8
4
5
6
7
RX IN
DR OUT
LTC1334
RS422RS232/EIA562
LTC1334 • F17
100Ω
13
11
9
19 24
232217
8
TX OUT
TX OUT
RX IN
RX IN
5V
4
5
6
7
LTC1334
Figure 17. Typical RS232/EIA562 to RS422 Level Translator
Figure 16. Typical Cable Repeater for RS422 Interface
1/2 LTC1334
TX OUT
RX IN
LTC1334 • F16
100Ω
4
5
6
8
23
2224
7
5V
1/2 LTC1334
1/2 LTC1334
1/2 LTC1334
LTC1334 • F15
100Ω
22
23
8
24
8
17
18
19
5V
5V
RX OUT
RX OUT
RX OUT
DR ENABLE
DR ENABLE
DR IN
DR IN
5
4
8
5V
4
5
6
7
11
10
13
24
12
100Ω
Figure 15. Typical Connection for RS422 Interface
A typical RS422 connection (Figure 15) allows one driver
and ten receivers on a twisted pair of wires terminated with
a 100Ω resistor at one end.
A typical twisted-pair line repeater is shown in Figure 16.
As data transmission rate drops with increased cable
length, repeaters can be inserted to improve transmission
rate or to transmit beyond the RS422 4000-foot limit.
The LTC1334 can be used to translate RS232 to RS422
interface levels or vice versa as shown in Figure 17. One
port is configured as an RS232 transceiver and the other
as an RS485 transceiver.
Using two LTC1334s as level translators, the RS232/
EIA562 interface distance can be extended to 4000 feet
with twisted-pair wires (Figure 18).
AppleTalk
®
/LocalTalk
®
Applications
Two AppleTalk applications are shown in Figure 19 and 20
with the LTC1323 and the LTC1334.
AppleTalk and LocalTalk are registered trademarks of Apple Computer, Inc.
