Datasheet

11
LTC1344
TYPICAL APPLICATIONS N
U
Cable Selectable Multiprotocol DTE Port with DB-25 Connector
LTC1343
1
2
4
3
8
5
6
7
9
10
39
38
37
36
35
34
33
32
31
30
29
28
27
26
21
19
18
17
12
13
14
15
16
40
23
20
22
11
25
CTRL
LATCH
INVERT
423 SET
DCE
M2
M1
M0
R2
R3
R4
R1
100k
TXD A
TXD B
SCTE A
SCTE B
RXD A
RXD B
RXC A
RXC B
RXC A
RXC B
RXD A
RXD B
RTS A
RTS B
DTR A
DTR B
DCD A
DCD B
DSR A
DSR B
CTS A
CTS B
DCD A
DCD B
DTR A
DTR B
RTS A
RTS B
DTE DCE
20 22 23 24 1
M0M1M2
DCE/
DTE
13
121138
C6
100pF
C7
100pF
19171815161097645
2
44
C2
1µF
C4
3.3µF
C10
1µF
C13
3.3µF
C5
1µF
C1
1µF
43
42
41
14
V
EE
V
CC
V
CC
5V
2
14
24
11
15
12
17
9
3
16
7
1
4
19
20
23
8
10
6
22
5
13
25
21
18
1344 TA03
DB-25 CONNECTOR
LTC1344
C8
100pF
R1
C3
1µF
GND
LB
V
CC
V
CC
V
CC
V
CC
V
CC
V
CC
EC
24
LTC1343
1
2
4
3
8
5
6
7
9
10
39
38
37
36
35
34
33
32
31
30
29
28
27
26
21
19
18
17
12
13
14
15
16
40
23
20
22
11
25
CTRL
LATCH
INVERT
423 SET
DCE
M2
M1
M0
R2
R3
R4
R2
100k
44
C12
1µF
C9
1µF
43
42
41
C11
1µF
GND
LB
EC
R1
DTE_TXD/DCE_RXD
DTE_SCTE/DEC_RXC
DTE_TXC/DCE_TXC
DTE_RXC/DCE_SCTE
DTE_RXD/DCE_TXD
DTE_RTS/DCE_CTS
DTE_DTR/DCE_DSR
DTE_DCD/DCE_DCD
DTE_DSR/DCE_DTR
DTE_CTS/ DCE_RTS
LB
SGND
SHIELD
CTS A
CTS B
DSR A
DSR B
CHARGE
PUMP
CHARGE
PUMP
D1
D2
D3
D4
TXC A
TXC B
SCTE A
SCTE B
TXD A
TXD B
TXC A
TXC B
R5
10k
R4
10k
DCE/DTE
M1
M0
V
CC
V
CC
D1
D2
D3
D4
24
R3
10k
V
CC
CABLE WIRING FOR MODE SELECTION
MODE PIN 18 PIN 21
V.35 PIN 7 PIN 7
EIA-530, RS449, NC PIN 7
V.36, X.21
RS232 PIN 7 NC
CABLE WIRING FOR DTE/DCE
SELECTION
MODE PIN 25
DTE PIN 7
DCE NC
21
LATCH
+
+
Information furnished by Linear Technology Corporation is believed to be accurate and reliable.
However, no responsibility is assumed for its use. Linear Technology Corporation makes no represen-
tation that the interconnection of its circuits as described herein will not infringe on existing patent rights.