LTC1545
Software-Selectable
Multiprotocol Transceiver
FEATURES
s
s
DESCRIPTIO
s
s
s
s
Software-Selectable Transceiver Supports:
RS232, RS449, EIA530, EIA530-A, V.35, V.36, X.21
TUV/Detecon Inc. Certified NET1 and NET2
Compliant (Test Report No. NET2/071601/98)
TBR2 Compliant (Test Report No. CTR2/071601/98)
Software-Selectable Cable Termination Using
the LTC1344A
Complete DTE or DCE Port with LTC1543, LTC1344A
Operates from Single 5V Supply with LTC1543
APPLICATIO S
s
s
s
The LTC
®
1545 is a 5-driver/5-receiver multiprotocol trans-
ceiver. The LTC1545 and LTC1543 form the core of a
complete software-selectable DTE or DCE interface port that
supports the RS232, RS449, EIA530, EIA530-A, V.35, V.36
or X.21 protocols. Cable termination may be implemented
using the LTC1344A software-selectable cable termination
chip or by using existing discrete designs.
The LTC1545 runs from a 5V supply and the charge pump on
the LTC1543. The part is available in a 36-lead SSOP surface
mount package.
Data Networking
CSU and DSU
Data Routers
, LTC and LT are registered trademarks of Linear Technology Corporation.
TYPICAL APPLICATIO
RL
TM
RI
LL
CTS
DSR
DTE or DCE Multiprotocol Serial Interface with DB-25 Connector
DCD
DTR
RTS
RXD
RXC
TXC
SCTE
TXD
LTC1545
D5
R5
R4
D4
D3
R3
R2
R1
D2
D1
R3
R2
R1
LTC1543
D3
D2
D1
21
25
*
18 13 5
22 6
10 8
23 20 19 4
1
7
16 3
9
17
12 15 11 24 14
DB-25 CONNECTOR
U
LTC1344A
2
U
U
CTS B
DSR B
DSR A (107)
CTS A (106)
DTR B
DTR A (108)
RTS B
RTS A (105)
SHIELD (101)
SG (102)
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)
TXC B
TXC A (114)
RL A (140)
TM A (142)
RI A (125)
LL A (141)
*OPTIONAL
1545 TA01
1
LTC1545
ABSOLUTE
MAXIMUM
RATINGS
(Note 1)
PACKAGE/ORDER INFORMATION
TOP VIEW
V
CC
V
DD
D1
D2
D3
R1
R2
R3
D4
1
2
3
4
5
6
7
8
9
R1
R2
R3
D4
R4
R5
D5
G PACKAGE
36-LEAD PLASTIC SSOP
D3
D1
D2
36 V
EE
35 GND
34 D1 A
33 D1 B
32 D2 A
31 D2 B
30 D3/R1 A
29 D3/R1 B
28 R2 A
27 R2 B
26 R3 A
25 R3 B
24 D4 A
23 R4 A
22 R5 A
21 D5 A
20 V
DD
19 V
CC
Supply Voltage
V
CC
..................................................................... 6.5V
V
EE
........................................................ – 10V to 0.3V
V
DD
....................................................... – 0.3V to 10V
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)
Short-Circuit Duration
Transmitter Output ..................................... Indefinite
Receiver Output .......................................... Indefinite
V
EE
.................................................................. 30 sec
Operating Temperature Range
LTC1545C .............................................. 0°C to 70°C
LTC1545I ........................................... – 40°C to 85°C
Storage Temperature Range ................ – 65°C to 150°C
Lead Temperature (Soldering, 10 sec)................. 300°C
ORDER PART
NUMBER
LTC1545CG
LTC1545IG
R4 10
M0 11
M1 12
M2 13
DCE/DTE 14
D4ENB 15
R4EN 16
R5 17
D5 18
T
JMAX
= 150°C,
θ
JA
= 65°C/ W
Consult factory for Military grade parts.
ELECTRICAL CHARACTERISTICS
The
q
denotes specifications which apply over the full operating temperature range, otherwise specifications are at T
A
= 25°C.
V
CC
= 5V, V
DD
= 8V, V
EE
= – 7V for V.28, – 5.5V for V.10, V.11 (Notes 2, 3)
SYMBOL
Supplies
I
CC
V
CC
Supply Current (DCE Mode,
All Digital Pins = GND or V
CC
)
RS530, RS530-A, X.21 Modes, No Load
RS530, RS530-A, X.21 Modes, Full Load
V.28 Mode, No Load
V.28 Mode, Full Load
No-Cable Mode, D4ENB = HIGH
RS530, RS530-A, X.21 Modes, No Load
RS530, X.21 Modes, Full Load
RS530-A, Full Load
V.28 Mode, No Load
V.28 Mode, Full Load
No-Cable Mode, D4ENB = HIGH
RS530, RS530-A, X.21 Modes, NoLoad
RS530, RS530-A, X.21 Modes, Full Load
V.28 Mode, No Load
V.28 Mode, Full Load
No-Cable Mode, D4ENB = HIGH
RS530, RS530-A, X.21 Modes, Full Load
V.28 Mode, Full Load
q
q
q
q
q
q
q
q
q
q
q
q
q
q
q
q
PARAMETER
CONDITIONS
MIN
TYP
2.7
110
1
1
10
2.0
23
34
1
12
10
0.3
0.3
1
13.5
10
340
64
MAX
5
150
3
3
500
4.0
35
50
3
18
500
2
2
3
18
500
UNITS
mA
mA
mA
mA
µA
mA
mA
mA
mA
mA
µA
mA
mA
mA
mA
µA
mW
mW
I
EE
V
EE
Supply Current (DCE Mode,
All Digital Pins = GND or V
CC
)
I
DD
V
DD
Supply Current (DCE Mode,
All Digital Pins = GND or V
CC
)
P
D
Internal Power Dissipation (DCE Mode,
(All Digital Pins = GND or V
CC
)
2
U
W
U
U
W W
W
LTC1545
ELECTRICAL CHARACTERISTICS
The
q
denotes specifications which apply over the full operating temperature range, otherwise specifications are at T
A
= 25°C.
V
CC
= 5V, V
DD
= 8V, V
EE
= – 7V for V.28, – 5.5V for V.10, V.11 (Notes 2, 3)
SYMBOL PARAMETER
Logic Inputs and Outputs
V
IH
V
IL
I
IN
Logic Input High Voltage
Logic Input Low Voltage
Logic Input Current
D1, D2, D3, D4, D5
M0, M1, M2, DCE, D4ENB, R4EN = GND (LTC1545C)
M0, M1, M2, DCE, D4ENB, R4EN = GND (LTC1545I)
M0, M1, M2, DCE, D4ENB, R4EN = V
CC
I
O
= – 4mA
I
O
= 4mA
0V
≤
V
O
≤
V
CC
M0 = M1 = M2 = V
CC
, 0V
≤
V
O
≤
V
CC
R
L
= 1.95k (Figure 1)
R
L
= 50Ω (Figure 1)
R
L
= 50Ω (Figure 1)
R
L
= 50Ω (Figure 1)
R
L
= 50Ω (Figure 1)
R
L
= 50Ω (Figure 1)
V
OUT
= GND
– 0.25V
≤
V
O
≤
0.25V, Power Off or
No-Cable Mode or Driver Disabled
LTC1545C (Figures 2, 5)
LTC1545I (Figures 2, 5)
LTC1545C (Figures 2, 5)
LTC1545I (Figures 2, 5)
LTC1545C (Figures 2, 5)
LTC1545I (Figures 2, 5)
LTC1545C (Figures 2, 5)
LTC1545I (Figures 2, 5)
(Figures 2, 5)
– 7V
≤
V
CM
≤
7V
– 7V
≤
V
CM
≤
7V
– 10V
≤
V
A,B
≤
10V
– 10V
≤
V
A,B
≤
10V
(Figures 2, 6)
LTC1545C (Figures 2, 6)
LTC1545I (Figures 2, 6)
LTC1545C (Figures 2, 6)
LTC1545I (Figures 2, 6)
LTC1545C (Figures 2, 6)
LTC1545I (Figures 2, 6)
q
q
q
q
q
q
q
q
q
q
q
q
q
q
q
q
q
q
q
q
q
q
q
q
q
q
q
q
q
q
q
q
q
CONDITIONS
MIN
2
TYP
MAX
UNITS
V
0.8
– 100
– 120
3
– 50
– 50
– 50
4.5
0.3
40
±1
±5
0.5V
ODO
±2
0.67V
ODO
0.8
50
±10
– 30
– 30
±10
V
µA
µA
µA
µA
V
V
mA
µA
V
V
V
OH
V
OL
I
OSR
I
OZR
V
ODO
V
ODL
∆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
t
PHL
∆t
Output High Voltage
Output Low Voltage
Output Short-Circuit Current
Three-State Output Current
Open Circuit Differential Output Voltage
Loaded Differential Output Voltage
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
Input to Output
Input to Output Difference,
t
PLH
– t
PHL
V.11 Driver
0.2
3
0.2
±150
±
1
2
2
20
20
20
20
0
0
15
15
40
40
40
40
3
3
3
– 0.2
15
15
30
15
50
50
50
50
0
0
4
4
80
90
80
90
16
21
0.2
40
±0.66
±100
25
35
65
75
65
75
12
17
V
V
V
mA
µA
ns
ns
ns
ns
ns
ns
ns
ns
ns
V
mV
mA
kΩ
ns
ns
ns
ns
ns
ns
ns
V.11 Receiver
3
LTC1545
ELECTRICAL CHARACTERISTICS
The
q
denotes specifications which apply over the full operating temperature range, otherwise specifications are at T
A
= 25°C.
V
CC
= 5V, V
DD
= 8V, V
EE
= – 7V for V.28, – 5.5V for V.10, V.11 (Notes 2, 3)
SYMBOL
V.10 Driver
V
O
V
T
I
SS
I
OZ
t
r
, t
f
t
PLH
t
PHL
V
TH
∆V
TH
I
IN
R
IN
t
r
, t
f
t
PLH
t
PHL
∆t
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 Hysterisis
Receiver Input Impedance
Rise or Fall Time
Input to Output
Input to Output
– 15V
≤
V
A
≤
15V
(Figures 4, 8)
(Figures 4, 8)
(Figures 4, 8)
q
q
PARAMETER
Output Voltage
Output Voltage
Short-Circuit Current
Output Leakage Current
Rise or Fall Time
Input to Output
Input to Output
Receiver Input Threshold Voltage
Receiver Input Hysteresis
Receiver Input Current
Receiver Input Impedance
Rise or Fall Time
Input to Output
Input to Output
Input to Output Difference,
t
PLH
– t
PHL
CONDITIONS
Open Circuit, R
L
= 3.9k
R
L
= 450Ω (Figure 3)
R
L
= 450Ω (Figure 3)
V
O
= GND
– 0.25V
≤
V
O
≤
0.25V, Power Off or
No-Cable Mode or Driver Disabled
R
L
= 450Ω, C
L
= 100pF (Figures 3, 7)
R
L
= 450Ω, C
L
= 100pF (Figures 3, 7)
R
L
= 450Ω, C
L
= 100pF (Figures 3, 7)
q
q
q
q
q
MIN
±4
±3.6
0.9V
O
TYP
MAX
±6
UNITS
V
V
±150
±0.1
2
1
1
– 0.25
25
15
30
15
55
109
60
q
q
q
q
q
q
q
mA
µA
µs
µs
µs
±100
V.10 Receiver
0.25
50
±0.66
V
mV
mA
kΩ
ns
ns
ns
ns
±10
±150
±1
4
1.3
1.3
1.5
2
3
1.6
0.1
5
15
60
150
100
450
0.3
7
±100
30
2.5
2.5
0.8
V
V
mA
µA
V/µs
µs
µs
V
V
V
kΩ
ns
ns
ns
– 10V
≤
V
A
≤
10V
– 10V
≤
V
A
≤
10V
(Figures 4, 8)
(Figures 4, 8)
(Figures 4, 8)
(Figures 4, 8)
Open Circuit
R
L
= 3k (Figure 3)
V
O
= GND
– 0.25V
≤
V
O
≤
0.25V, Power Off or
No-Cable Mode or Driver Disabled
R
L
= 3k, C
L
= 2500pF (Figures 3, 7)
R
L
= 3k, C
L
= 2500pF (Figures 3, 7)
R
L
= 3k, C
L
= 2500pF (Figures 3, 7)
q
q
±5
±8.5
V.28 Receiver
q
q
q
q
Note 1:
Absolute Maximum Ratings are those values beyond which the life
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, V
DD
= 8V, V
EE
= – 7V for V.28,
– 5.5V for V.10, V.11 and T
A
= 25°C.
4
LTC1545
PIN FUNCTIONS
V
CC
(Pins 1, 19):
Positive Supply for the Transceivers.
4.75V
≤
V
CC
≤
5.25V. Connect a 1µF capacitor to ground.
V
DD
(Pins 2, 20):
Positive Supply Voltage for V.28. Con-
nect to V
DD
Pin 3 on LTC1543 or 8V supply. Connect a 1µF
capacitor to ground.
D1 (Pin 3):
TTL Level Driver 1 Input.
D2 (Pin 4):
TTL Level Driver 2 Input.
D3 (Pin 5):
TTL Level Driver 3 Input.
R1 (Pin 6):
CMOS Level Receiver 1 Output.
R2 (Pin 7):
CMOS Level Receiver 2 Output.
R3 (Pin 8):
CMOS Level Receiver 3 Output.
D4 (Pin 9):
TTL Level Driver 4 Input.
R4 (Pin 10):
CMOS Level Receiver 4 Output.
M0 (Pin 11):
TTL Level Mode Select Input 0 with Pull-Up
to V
CC
.
M1 (Pin 12):
TTL Level Mode Select Input 1 with Pull-Up
to V
CC
.
M2 (Pin 13):
TTL Level Mode Select Input 2 with Pull-Up
to V
CC
.
DCE/DTE (Pin 14):
TTL Level Mode Select Input with
Pull-Up to V
CC
. Logic high enables Driver 3. Logic low
enables Receiver 1.
D4ENB (Pin 15):
TTL Level Enable Input with Pull-Up to
V
CC
. Logic low enables Driver 4.
R4EN (Pin 16):
TTL Level Enable Input with Pull-Up to V
CC
.
Logic high enables Receiver 4.
R5 (Pin 17):
CMOS Level Receiver 5 Output.
D5 (Pin 18):
TTL Level Driver 5 Input.
D5 A (Pin 21):
Driver 5 Output.
R5 A (Pin 22):
Receiver 5 Input.
R4 A (Pin 23):
Receiver 4 Input.
D4 A (Pin 24):
Driver 4 Input.
R3 B (Pin 25):
Receiver 3 Noninverting Input.
R3 A (Pin 26):
Receiver 3 Inverting Input.
R2 B (Pin 27):
Receiver 2 Noninverting Input.
R2 A (Pin 28):
Receiver 2 Inverting Input.
D3/R1 B (Pin 29):
Receiver 1 Noninverting Input and
Driver 3 Noninverting Output.
D3/R1 A (Pin 30):
Receiver 1 Inverting Input and Driver 3
Inverting Output.
D2 B (Pin 31):
Driver 2 Noninverting Output.
D2 A (Pin 32):
Driver 2 Inverting Output.
D1 B (Pin 33):
Driver 1 Noninverting Output.
D1 A (Pin 34):
Driver 1 Inverting Output.
GND (Pin 35):
Ground.
V
EE
(Pin 36):
Negative Supply Voltage. Connect to V
EE
Pin
26 on LTC1543. Connect a 1µF capacitor to ground.
TEST CIRCUITS
A
R
L
V
OD
R
L
B
V
OC
1545 F02
Figure 1. V.11 Driver Test Circuit
U
U
U
B
A
R
L
100Ω
C
L
100pF
C
L
100pF
B
A
R
15pF
1545 F01
Figure 2. V.11 Driver/Receiver AC Test Circuit
5
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