LTC1343
Software-Selectable
Multiprotocol Transceiver
FEATURES
s
DESCRIPTIO
s
s
s
s
s
Software-Selectable Transceiver Supports:
RS232, RS449, EIA-530, EIA-530-A, V.35, V.36,
X.21
NET1 and NET2 Compliant
Software-Selectable Cable Termination Using
the LTC1344
4-Driver/4-Receiver Configuration Provides a
Complete 2-Chip DTE or DCE Port
Operates from Single 5V Supply
Internal Echoed Clock and Loop-Back Logic
APPLICATIO S
s
s
s
Data Networking
CSU and DSU
Data Routers
, LTC and LT are registered trademarks of Linear Technology Corporation.
The LTC
®
1343 is a 4-driver/4-receiver multiprotocol trans-
ceiver that operates from a single 5V supply. Two LTC1343s
form the core of a complete software-selectable DTE or DCE
interface port that supports the RS232, RS449, EIA-530,
EIA-530-A, V.35, V.36 or X.21 protocols. Cable termination
may be implemented using the LTC1344 software-selectable
cable termination chip or by using existing discrete designs.
The LTC1343 runs from a single 5V supply using an internal
charge pump that requires only five space saving surface mount
capacitors. The mode pins are latched internally to allow sharing
of the select lines between multiple interface ports.
Software-selectable echoed clock and loop-back modes help
eliminate the need for external glue logic between the serial
controller and line transceiver. The part features a flow-
through architecture to simplify EMI shielding and is available
in the 44-lead SSOP surface mount package.
TYPICAL APPLICATIO
CTS
DSR
DCD
DTE Multiprotocol Serial Interface with DB-25 Connector
DTR
RTS
RL
TM
RXD
RXC
TXC
SCTE
TXD
LL
LTC1343
D4
R4
R3
R2
R1
D3
D2
D1
R4
R3
R2
LTC1343
D4
R1
D3
D2
D1
13 5
22 6
10 8
23 20 19
4
21
1
7
25
16 3
9
17 12 15
11 24 14 2
DB-25 CONNECTOR
U
LTC1344
18
U
U
DSR B
DSR A (107)
RL A (140)
CTS B
CTS A (106)
DTR B
DTR A (108)
RTS B
RTS A (105)
SHIELD (101)
SGND (102)
TM A (142)
RXD B
RXD A (104)
RXC B
RXC A (115)
DCD B
DCD A (109)
SCTE B
SCTE A (113)
TXD B
TXD A (103)
LL A (141)
TXC B
TXC A (114)
1343 TA01
1
LTC1343
ABSOLUTE
MAXIMUM
RATINGS
(Note 1)
PACKAGE/ORDER INFORMATION
TOP VIEW
V
DD
C1
+
PWRV
CC
C1
–
Supply Voltage ....................................................... 6.5V
Input Voltage
Transmitters ........................... – 0.3V to (V
CC
+ 0.3V)
Receivers ............................................... – 18V to 18V
Logic Pins .............................. – 0.3V to (V
CC
+ 0.3V)
Output Voltage
Transmitters ................. (V
EE
– 0.3V) to (V
DD
+ 0.3V)
Receivers ................................ – 0.3V to (V
CC
+ 0.3V)
Logic Pins .............................. – 0.3V to (V
CC
+ 0.3V)
V
EE
........................................................ – 10V to 0.3V
V
DD
....................................................... – 0.3V to 10V
Short-Circuit Duration
Transmitter Output ..................................... Indefinite
Receiver Output .......................................... Indefinite
V
EE
.................................................................. 30 sec
Operating Temperature Range
LTC1343C .............................................. 0°C to 70°C
LTC1343I ........................................... – 40°C to 85°C
Storage Temperature Range ................ – 65°C to 150°C
Lead Temperature (Soldering, 10 sec)................. 300°C
1
2
3
4
5
6
7
8
9
D3
D2
D1
CHARGE PUMP
44 C2
+
43 C2
–
42 V
EE
41 PGND
40 GND
39 D1 A
38 D2 A
37 D2 B
36 D3 A
35 D3 B
34 D4 A
D4
33 D4 B
32 R1 A
R1
31 R1 B
30 R2 A
R2
29 R2 B
28 R3 A
R3
27 R3 B
26 R4 A
25 423 SET
24 EC
23 LB
GW PACKAGE
44-LEAD PLASTIC SSOP
ORDER PART
NUMBER
LTC1343CGW
LTC1343IGW
D1
D2
D3
V
CC
D4
D4EN 10
INVERT 11
R1EN 12
R1O 13
R2O 14
R3O 15
R4O 16
M0 17
M1 18
M2 19
CTRL/CLK 20
DCE/DTE 21
LATCH 22
R4
T
JMAX
= 150°C,
θ
JA
= 65°C/ W
Consult factory for Military grade parts.
The
q
denotes specifications which apply over the full operating
temperature range, otherwise specifications are at T
A
= 25°C. V
CC
= 5V (Notes 2, 3)
SYMBOL
Supplies
I
CC
V
CC
Supply Current (DCE Mode,
All Digital Pins = GND or V
CC
)
V.10 Mode, No Load
V.10 Mode, Full Load
RS530, RS530-A, X.21 Modes, No Load
RS530, RS530-A, X.21 Modes, Full Load
V.35 Mode, No Load
V.35 Mode, Full Load
V.28 Mode, No Load
V.28 Mode, Full Load
No-Cable Mode
V.10 Mode, Full Load
RS530, RS530-A, X.21 Modes, Full Load
V.35 Mode, Full Load
V.28 Mode, Full Load
Any Mode, No Load
V.28 Mode, with Load
V.28 Mode, Full Load
V.35 Mode, Full Load
– 40°C
≤
T
A
≤
85°C
V.10, RS530, RS530A, X.21 Modes, Full Load
– 40°C
≤
T
A
≤
85°C
q
q
q
q
q
q
q
q
q
q
q
q
ELECTRICAL CHARACTERISTICS
PARAMETER
CONDITIONS
MIN
TYP
12
80
80
160
20
115
20
30
0.05
400
680
500
150
MAX
UNITS
mA
mA
mA
mA
mA
mA
mA
mA
mA
mW
mW
mW
mW
V
V
V
V
V
V
V
150
200
160
90
1
P
D
Internal Power Dissipation (DCE Mode,
All Digital Pins = GND or V
CC
)
V
+
V
–
Positive Charge Pump Output Voltage
Negative Charge Pump Output Voltage
8.5
8.0
– 7.8
– 5.8
– 5.5
– 5.0
– 4.8
9.1
7.0
– 8.4
– 6.7
– 6.1
2
U
W
U
U
W W
W
LTC1343
The
q
denotes specifications which apply over the full operating
temperature range, otherwise specifications are at T
A
= 25°C. V
CC
= 5V (Notes 2, 3)
SYMBOL
t
r
V
IH
V
IL
I
IN
V
OH
V
OL
I
OSR
I
OZR
V.11 Driver
V
OD
∆V
OD
V
OC
∆V
OC
I
SS
I
OZ
t
r
, t
f
t
PLH
t
PHL
∆t
t
SKEW
V
TH
∆V
TH
I
IN
R
IN
t
r
, t
f
t
PLH
Differential Output Voltage
Open Circuit, R
L
= 1.95k
R
L
= 50Ω (Figure 1),
V
OD
at 50Ω > 1/2 V
OD
at R
L
= 1.95k
R
L
= 50Ω (Figure 1)
R
L
= 50Ω (Figure 1)
R
L
= 50Ω (Figure 1)
– 0.25V
≤
V
O
≤
0.25V, Power Off or
No-Cable Mode or Driver Disabled
– 0.25V
≤
V
O
≤
0.25V, Power Off or
No-Cable Mode or Driver Disabled
(Figures 2, 6)
(Figures 2, 6), 0°C
≤
T
A
≤
70°C
(Figures 2, 6), – 40°C
≤
T
A
≤
85°C
(Figures 2, 6), 0°C
≤
T
A
≤
70°C
(Figures 2, 6), – 40°C
≤
T
A
≤
85°C
(Figures 2, 6), 0°C
≤
T
A
≤
70°C
(Figures 2, 6), – 40°C
≤
T
A
≤
85°C
(Figures 2, 6)
– 7V
≤
V
CM
≤
7V, 0°C
≤
T
A
≤
70°C
– 7V
≤
V
CM
≤
7V, – 40°C
≤
T
A
≤
85°C
– 7V
≤
V
CM
≤
7V, 0°C
≤
T
A
≤
70°C
– 7V
≤
V
CM
≤
7V, – 40°C
≤
T
A
≤
85°C
– 10V
≤
V
A, B
≤
10V
– 10V
≤
V
A, B
≤
10V
(Figures 2, 7)
(Figures 2, 7), CTRL = GND, 0°C
≤
T
A
≤
70°C
CTRL = V
CC
, 0°C
≤
T
A
≤
70°C
(Figures 2, 7), CTRL = GND, – 40°C
≤
T
A
≤
85°C
CTRL = V
CC
, – 40°C
≤
T
A
≤
85°C
q
q
q
q
q
q
q
q
q
q
q
q
q
q
q
q
q
q
q
q
q
ELECTRICAL CHARACTERISTICS
PARAMETER
Supply Rise Time
Logic Input High Voltage
Logic Input Low Voltage
Logic Input Current
Output High Voltage
Output Low Voltage
Output Short-Circuit Current
Three-State Output Current
CONDITIONS
No-Cable Mode or Power-Up to Turn On
q
q
q
MIN
TYP
2
MAX
UNITS
ms
V
Logic Inputs and Outputs
2
0.8
±10
3
– 60
– 70
±1
±6
4.5
0.3
0.8
60
70
V
µA
V
V
mA
mA
µA
V
V
V
V
V
mA
µA
ns
ns
ns
ns
ns
ns
ns
ns
0.2
0.3
15
40
60
±0.50
20
35
25
32
15
80
400
80
400
115
130
V
V
mV
mV
mA
kΩ
ns
ns
ns
ns
ns
I
O
= – 4mA
I
O
= 4mA
0V
≤
V
O
≤
V
CC
, 0°C
≤
T
A
≤
70°C
0V
≤
V
O
≤
V
CC
, – 40°C
≤
T
A
≤
85°C
M0 = M1 = M2 = V
CC
, 0V
≤
V
O
≤
V
CC
q
q
q
q
±2
Change in Magnitude of Differential
Output Voltage
Common Mode Output Voltage
Change in Magnitude of Common Mode
Output Voltage
Short-Circuit Current
Output Leakage Current
Rise or Fall Time
Input to Output
Input to Output
Input to Output Difference,
t
PLH
– t
PHL
Output to Output Skew
Input Threshold Voltage
Input Hysteresis
Input Current (A, B)
Input Impedance
Rise or Fall Time
Input to Output
0.2
3.0
0.2
±150
±0.01
4
25
25
25
25
0
0
13
55
55
55
55
3
3
3
– 0.2
– 0.3
±100
25
80
90
80
90
17
25
V.11 Receiver
3
LTC1343
The
q
denotes specifications which apply over the full operating
temperature range, otherwise specifications are at T
A
= 25°C. V
CC
= 5V (Notes 2, 3)
SYMBOL
t
PHL
PARAMETER
Input to Output
CONDITIONS
(Figures 2, 7), CTRL = GND, 0°C
≤
T
A
≤
70°C
CTRL = V
CC
, 0°C
≤
T
A
≤
70°C
(Figures 2, 7), CTRL = GND, –40°C
≤
T
A
≤
85°C
CTRL = V
CC
, –40°C
≤
T
A
≤
85°C
∆t
V.35 Driver
V
OD
I
OH
I
OL
I
OZ
t
r
, t
f
t
PLH
t
PHL
∆t
t
SKEW
V
TH
∆V
TH
I
IN
R
IN
t
r
, t
f
t
PLH
t
PHL
∆t
V.10 Driver
V
O
Output Voltage
Open Circuit, R
L
= 3.9k
R
L
= 450Ω (Figure 4)
V
O
at 450Ω > 0.9 V
O
at R
L
= 3.9k
Driver 1 Only
V
O
= GND; EIA-530, X.21, EIA-530-A Modes
– 0.25V
≤
V
O
≤
0.25V, Power Off or
No-Cable Mode or Driver Disabled
(Figures 4, 8), R
L
= 450Ω, C
L
= 100pF
R
423SET
= 100k
(Figures 4, 8), R
L
= 450Ω, C
L
= 100pF
R
423SET
= 100k
(Figures 4, 8), R
L
= 450Ω, C
L
= 100pF
R
423SET
= 100k
q
q
q
q
q
ELECTRICAL CHARACTERISTICS
MIN
35
25
0
0
TYP
80
400
80
400
5
5
MAX
115
130
17
25
6.0
±0.66
– 9.4
12.6
±100
75
90
75
90
17
25
UNITS
ns
ns
ns
ns
ns
ns
V
V
mA
mA
µA
ns
ns
ns
ns
ns
ns
ns
ns
Input to Output Difference,
t
PLH
– t
PHL
(Figures 2, 7), 0°C
≤
T
A
≤
70°C
(Figures 2, 7), –40°C
≤
T
A
≤
85°C
Open Circuit
With Load, – 4.0V
≤
V
CM
= 4.0V (Figure 3)
V
A, B
= 0V
V
A, B
= 0V
– 0.25V
≤
V
A, B
≤
0.25V
(Figures 3, 6)
(Figures 3, 6), 0°C
≤
T
A
≤
70°C
(Figures 3, 6), –40°C
≤
T
A
≤
85°C
(Figures 3, 6), 0°C
≤
T
A
≤
70°C
(Figures 3, 6), –40°C
≤
T
A
≤
85°C
(Figures 3, 6), 0°C
≤
T
A
≤
70°C
(Figures 3, 6), –40°C
≤
T
A
≤
85°C
(Figures 3, 6)
– 2V
≤
(V
A
+ V
B
)/2
≤
2V (Figure 3)
– 2V
≤
(V
A
+ V
B
)/2
≤
2V (Figure 3)
– 10V
≤
V
A, B
≤
10V
– 10V
≤
V
A, B
≤
10V
(Figures 3, 7)
(Figures 3, 7), 0°C
≤
T
A
≤
70°C
(Figures 3, 7), –40°C
≤
T
A
≤
85°C
(Figures 3, 7), 0°C
≤
T
A
≤
70°C
(Figures 3, 7), –40°C
≤
T
A
≤
85°C
(Figures 3, 7), 0°C
≤
T
A
≤
70°C
(Figures 3, 7), –40°C
≤
T
A
≤
85°C
Differential Output Voltage
Transmitter Output High Current
Transmitter Output Low Current
Transmitter Output Leakage Current
Rise or Fall Time
Input to Output
Input to Output
Input to Output Difference,
t
PLH
– t
PHL
Output to Output Skew
Differential Receiver Input
Threshold Voltage
Receiver Input Hysteresis
Receiver Input Current (A, B)
Receiver Input Impedance
Rise or Fall Time
Input to Output
Input to Output
Input to Output Difference,
t
PLH
– t
PHL
q
q
q
q
±0.44
– 12.6
9.4
±0.55
– 11
11
±0.01
5
q
q
q
q
q
q
25
25
25
25
0
0
45
45
45
45
5
5
4
V.35 Receiver
q
q
q
q
– 0.2
11
20
32
15
80
80
100
100
4
4
±4.0
±3.6
0.2
40
±0.50
V
mV
mA
kΩ
ns
q
q
q
q
q
q
115
130
115
130
17
25
±6.0
ns
ns
ns
ns
ns
ns
V
V
I
SS
I
OZ
t
r
, t
f
t
PLH
t
PHL
Short-Circuit Current
Output Leakage Current
Rise or Fall Time
Input to Output
Input to Output
±150
±0.1
±100
mA
µA
4
8
8
µs
µs
µs
4
LTC1343
The
q
denotes specifications which apply over the full operating
temperature range, otherwise specifications are at T
A
= 25°C. V
CC
= 5V (Notes 2, 3)
SYMBOL
V
TH
∆V
TH
I
IN
R
IN
t
r
, t
f
t
PLH
t
PHL
V.28 Driver
V
O
I
SS
I
OZ
SR
t
PLH
t
PHL
V
THL
V
TLH
∆V
TH
R
IN
t
r
, t
f
t
PLH
t
PHL
Output Voltage
Short-Circuit Current
Output Leakage Current
Slew Rate
Input to Output
Input to Output
Input Low Threshold Voltage
Input High Threshold Voltage
Receiver Input Hysteresis
Receiver Input Impedance
Rise or Fall Time
Input to Output
Input to Output
– 15V
≤
V
A
≤
15V
(Figures 5, 9)
(Figures 5, 9), CTRL = 0V
CTRL = V
CC
(Figures 5, 9), CTRL = 0V
CTRL = V
CC
q
q
ELECTRICAL CHARACTERISTICS
PARAMETER
Receiver Input Threshold Voltage
Receiver Input Hysteresis
Receiver Input Current
Receiver Input Impedance
Rise or Fall Time
Input to Output
Input to Output
CONDITIONS
0°C
≤
T
A
≤
70°C
–7V
≤
V
CM
≤
7V, – 40°C
≤
T
A
≤
85°C
– 10V
≤
V
A
≤
10V
– 10V
≤
V
A
≤
10V
(Figures 5, 9)
(Figures 5, 9)
(Figures 5, 9)
Open Circuit
R
L
= 3k (Figure 4)
V
O
= GND
– 0.25V
≤
V
O
≤
0.25V, Power Off or
No-Cable Mode or Driver Disabled
(Figures 4, 8), R
L
= 3k, C
L
= 2500pF
(Figures 4, 8), R
L
= 3k, C
L
= 2500pF
(Figures 4, 8), R
L
= 3k, C
L
= 2500pF
q
q
q
q
q
MIN
– 0.2
– 0.3
TYP
MAX
0.2
0.3
UNITS
V
V
mV
mA
kΩ
ns
ns
ns
V.10 Receiver
11
20
30
15
350
350
50
±0.50
q
q
q
q
q
q
±5
±10
7.6
±150
±0.01
±100
30.0
1.6
1.6
1.4
2.5
2.5
0.8
1.0
7
V
V
mA
µA
V/µs
µs
µs
V
V
V
kΩ
ns
ns
ns
ns
ns
4.0
V.28 Receiver
q
q
q
q
2.0
0.1
3
1.4
0.4
5
15
110
330
170
480
800
800
Note 1:
Absolute Maximum Ratings are those beyond which the safety of a
device may be impaired.
Note 2:
All currents into device pins are positive; all currents out of device
are negative. All voltages are referenced to device ground unless otherwise
specified.
Note 3:
All typicals are given for V
CC
= 5V, C1 = C2 = C
VCC
= C
VDD
= 1µF,
C
VEE
= 3.3µF tantalum capacitors and T
A
= 25°C.
PIN FUNCTIONS
V
DD
(Pin 1):
Generated Positive Supply Voltage for
RS232. Connect a 1µF capacitor to ground.
C1
+
(Pin 2):
Capacitor C1 Positive Terminal. Connect a
1µF capacitor between C1
+
and C1
–
.
PWRV
CC
(Pin 3):
Positive Supply for the Charge Pump.
4.75V
≤
PWRV
CC
≤
5.25V. Tie to V
CC
(Pin 8) and bypass
with a 1µF capacitor to ground.
C1
–
(Pin 4):
Capacitor C1 Negative Terminal.
D1 (Pin 5):
TTL Level Driver 1 Input.
D2 (Pin 6):
TTL Level Driver 2 Input.
D3 (Pin 7):
TTL Level Driver 3 Input. Becomes a CMOS
level output when the chip is in the echoed clock mode
(EC = 0V).
U
U
U
5
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