19-1801; Rev 2; 6/04
+3.3V Multiprotocol Software-Selectable
Cable Terminators and Transceivers
General Description
The MAX3172/MAX3174 contain five software-selec-
table multiprotocol cable termination networks. Each
network is capable of terminating V.11 (RS-422, RS-
530, RS-530A, RS-449, V.36, and X.21) with a 100Ω dif-
ferential load, V.35 with a T-network load, or V.28
(RS-232) and V.10 (RS-423) with an open circuit load
for use with transceivers having on-chip termination.
The devices replace discrete resistor termination net-
works and expensive relays required for multiprotocol
termination. The MAX3172/MAX3174, along with the
MAX3170 and MAX3171/MAX3173, form a complete
+3.3V software-selectable DTE or DCE interface port
supporting V.11/RS-422, RS-530, RS-530A, V.36/RS-
449, V.35, V.28/RS-232, V.10/RS-423, and X.21 serial
interfaces.
In addition to the five multiprotocol cable termination
networks, the MAX3172/MAX3174 contain a 1Tx/1Rx
multiprotocol transceiver designed to use V+ and V-
generated by the MAX3171/MAX3173 charge pump.
The MAX3172/MAX3174 transceiver is software selec-
table between V.10 and V.28 modes of operation. The
MAX3172 features 10µs deglitching on the V.10/V.28
receiver input to facilitate unterminated operation, while
the MAX3174 is used in applications that do not require
deglitching on the serial handshake signals. These
devices are available in a 28-pin SSOP package.
Features
♦
Industry’s First +3.3V Multiprotocol Termination
Networks and Transceivers
♦
Certified TBR-1 and TBR-2 Compliant
(NET1 and NET2)
♦
Support V.28 (RS-232), V.11 (RS-422, RS-530, RS-
530A, RS-449, V.36, and X.21), V.10 and V.35
♦
3V/5V Logic-Compatible I/O
♦
Software-Selectable DTE/DCE
♦
Replace Discrete Resistor Termination Networks
and Expensive Relays
♦
10µs Receiver Input Deglitching (MAX3172 only)
♦
Available in Small 28-Pin SSOP Package
♦
Transmitter Output Fault Protected to ±15V,
Tolerates Cable Miswiring
MAX3172/MAX3174
Ordering Information
PART
MAX3172CAI
MAX3172EAI
MAX3174CAI
TEMP RANGE
0°C to +70°C
-40°C to +85°C
0°C to +70°C
PIN-PACKAGE
28 SSOP
28 SSOP
28 SSOP
________________________Applications
Data Networking
CSU and DSU
Data Routers
CTS
PCI Cards
Telecommunications
Pin Configuration appears at end of data sheet.
Typical Operating Circuit
DSR
DCD
DTR
RTS
LL
RXD
RXC
TXC
SCTE TXD
MAX3171
MAX3173
R3
R2
R1
D3
D2
D1
MAX3172
MAX3174
R3
R2
R1
D3
D2
D1
MAX3170
R4
D4
13 5
CTS B
CTS A
10 8
DSR B
DSR A
22 6
DCD B
DCD A
23 20 19 4
DTR B
DTR A
RTS B
RTS A
1
SHIELD
7
SG
DB-25 CONNECTOR
18
LL A
16 3
9 17
12 15 11 24 14 2
TXC B
TXC A
SCTE B
SCTE A
TXD B
TXD A
________________________________________________________________
Maxim Integrated Products
RXD B
RXD A
RXC B
RXC A
1
For price, delivery, and to place orders, please contact Maxim Distribution at 1-888-629-4642,
or visit Maxim’s website at www.maxim-ic.com.
+3.3V Multiprotocol Software-Selectable
Cable Terminators and Transceivers
MAX3172/MAX3174
ABSOLUTE MAXIMUM RATINGS
(All voltages referenced to GND unless otherwise noted.)
Supply Voltages
V
CC
......................................................................-0.3V to +4V
V+ (Note 1) ..........................................................-0.3V to +7V
V- (Note 1) ...........................................................+0.3V to -7V
V+ to V- (Note 1) ...............................................................13V
Logic Input Voltages
M0, M1, M2, DCE/DTE, INVERT, T4IN ................-0.3V to +6V
Logic Output Voltages
R4OUT...................................................-0.3V to (V
CC
+ 0.3V)
Short-Circuit Duration............................................Continuous
Transmitter Outputs
T4OUT ................................................................-15V to +15V
Short-Circuit Duration ........................................................60s
Receiver Input
R4INA .................................................................-15V to +15V
Termination Network Inputs (applied individually)
R_A, R_B ............................................................-15V to +15V
Continuous Power Dissipation (T
A
= +70°C)
28-Pin SSOP (derate 9.52mW/°C above +70°C) ........762mW
Operating Temperature Range
MAX3172CAI/MAX3174CAI ...............................0°C to +70°C
MAX3172EAI...................................................-40°C to +85°C
Junction Temperature ......................................................+150°C
Storage Temperature Range .............................-65°C to +150°C
Lead Temperature (soldering, 10s) .................................+300°C
Note 1:
V+ and V- can have maximum magnitudes of 7V, but their absolute difference cannot exceed 13V.
Stresses beyond those listed under “Absolute Maximum Ratings” may cause permanent damage to the device. These are stress ratings only, and functional
operation of the device at these or any other conditions beyond those indicated in the operational sections of the specifications is not implied. Exposure to
absolute maximum rating conditions for extended periods may affect device reliability.
ELECTRICAL CHARACTERISTICS
(V
CC
= +3.3V ± 5%, T
A
= T
MIN
to T
MAX
. Typical values are at V
CC
= +3.3V, T
A
= +25°C, unless otherwise noted. See Note 2 for V+
and V- input voltage conditions.)
PARAMETER
DC CHARACTERISTICS
Supply Current
(Digital Inputs = GND or V
CC
)
V+ Supply Current
(T4IN = GND)
I
CC
All modes V.10 receiver inactive
All modes V.10 receiver active
No-cable mode
I
V+
V.10/V.11/V.28/V.35 modes unloaded
V.10/V.11 modes T4OUT loaded
V.28/V.35 modes T4OUT loaded
No-cable mode
V- Supply Current
(T4IN = V
CC
)
I
V-
V.10/V.11/V.28/V.35 modes unloaded
V.10/V.11 modes T4OUT loaded
V.28/V.35 modes T4OUT loaded
TERMINATOR NETWORKS
(R_A, R_B)
Differential-Mode Impedance
V.35 Mode
Common-Mode Impedance
V.35 Mode
Differential-Mode Impedance
V.11 Mode
Network OFF Impedance
I
Z
Figure 1, -2V
≤
V
CM
≤
+2V
Figure 2, -2V
≤
V
CM
≤
+2V
Figure 1, -7V
≤
V
CM
≤
+7V
Switches open, -15V
≤
V
A
≤
+15V, V
B
= V
A
,
V
B
= GND or V
B
floating
90
135
100
50
104
153
104
150
110
165
110
Ω
Ω
Ω
kΩ
80
400
0.2
0.5
11.0
3.0
-0.4
-0.8
-11.0
-3.0
200
750
1.0
2.5
14.0
5.0
-1.0
-2.5
-14.0
-5.0
mA
mA
µA
SYMBOL
CONDITIONS
MIN
TYP
MAX
UNITS
LOGIC INPUTS
(M0, M1, M2, INVERT, DCE/DTE, T4IN)
Input High Voltage
Input Low Voltage
Logic Input Current
V
IH
V
IL
I
IH
, I
IL
V
IN
= V
CC
or GND
2.0
0.8
±1
V
V
µA
2
_______________________________________________________________________________________
+3.3V Multiprotocol Software-Selectable
Cable Terminators and Transceivers
ELECTRICAL CHARACTERISTICS (continued)
(V
CC
= +3.3V ± 5%, T
A
= T
MIN
to T
MAX
. Typical values are at V
CC
= +3.3V, T
A
= +25°C, unless otherwise noted. See Note 2 for V+
and V- input voltage conditions.)
PARAMETER
LOGIC OUTPUT
(R4OUT)
Output High Voltage
Output Low Voltage
Rise or Fall Time
Output Leakage Current
(Receiver Output Three-Stated)
TRANSMITTER OUTPUT
(T4OUT)
Output Leakage Current
Data Rate
RECEIVER INPUT
(R4INA)
Receiver Glitch Rejection
(MAX3172 only)
Receiver Input Resistance
Data Rate
V.10 TRANSMITTER
Output Voltage Swing
Loaded Output Voltage Swing
Short-Circuit Current
Rise or Fall Time
Transmitter Propagation Delay
Data Skew
V.10 RECEIVER
Threshold Voltage
Input Hysteresis
Receiver Propagation Delay
V
TH
∆V
TH
t
PHL
, t
PLH
| t
PHL
-
t
PLH
|
Figure 4
MAX3172
MAX3174
MAX3172CAI
Data Skew
Figure 4
MAX3172EAI
MAX3174
5
25
100
15
10
60
0.5
0.5
5
15
120
4
5
16
250
mV
mV
µs
ns
µs
ns
V
ODO
V
ODL
I
SC
t
r
, t
f
t
PHL
, t
PLH
| t
PHL
-
t
PLH
|
R
L
= 3.9kΩ, Figure 3
R
L
= 450Ω, Figure 3
T4OUT = GND
10% to 90%, R
L
= 450Ω, C
L
= 100pF,
Figure 3
R
L
= 450Ω, C
L
= 100pF, Figure 3
R
L
= 450Ω, C
L
= 100pF, Figure 3
±4.0
0.9
×
V
ODO
±100
2
2
50
±150
±4.4
±6.0
V
V
mA
µs
µs
ns
R
IN
Minimum pulse width passed
Maximum pulse width rejected
V.10 enabled, -10V
≤
V
R4INA
≤
+10V
V.28 enabled, -15V
≤
V
R4INA
≤
+15V
MAX3172
MAX3174
20
3
40
5
64
240
7
5
15
µs
kΩ
kbps
I
Z
-0.25V < V
T4OUT
< +0.25V,
power-off or no-cable mode
V.10/V.28
-100
240
100
µA
kbps
V
OH
V
OL
t
r
, t
f
I
SOURCE
= 1.0mA
I
SINK
= 1.6mA
10% to 90%, C
L
= 15pF
R4OUT = GND
R4OUT = V
CC
30
15
50
0.1
100
1
V
CC
- 1.0
0.4
V
V
ns
µA
SYMBOL
CONDITIONS
MIN
TYP
MAX
UNITS
MAX3172/MAX3174
_______________________________________________________________________________________
3
+3.3V Multiprotocol Software-Selectable
Cable Terminators and Transceivers
MAX3172/MAX3174
ELECTRICAL CHARACTERISTICS (continued)
(V
CC
= +3.3V ± 5%, T
A
= T
MIN
to T
MAX
. Typical values are at V
CC
= +3.3V, T
A
= +25°C, unless otherwise noted. See Note 2 for V+
and V- input voltage conditions.)
PARAMETER
V.28 TRANSMITTER
Output Voltage Swing
Short-Circuit Current
V
O
I
SC
R
L
= 3kΩ, Figure 3
Open circuit, Figure 3
T4OUT = GND
R
L
= 3kΩ,
C
L
= 2500pF
measured from +3V
to -3V or -3V to +3V,
Figure 3
MAX3172CAI
MAX3174CAI
MAX3172EAI
4
3
6
1
100
±25
±5.0
±5.4
±6.5
±60
30
30
30
µs
ns
V/µs
V
mA
SYMBOL
CONDITIONS
MIN
TYP
MAX
UNITS
Output Slew Rate
SR
R
L
= 7kΩ , C
L
= 150pF measured from
+3V to -3V or -3V to +3V, Figure 3
Transmitter Propagation Delay
Data Skew
V.28 RECEIVER
Input Threshold Low
Input Threshold High
Input Hysteresis
Receiver Propagation Delay
V
IL
V
IH
V
HYS
t
PHL
, t
PLH
| t
PHL
-
t
PLH
|
Figure 4
MAX3172
MAX3174
MAX3172CAI
Data Skew
Figure 4
MAX3172EAI
MAX3174
t
PHL
, t
PLH
| t
PHL
-
t
PLH
|
1.1
2.0
5
1.6
0.5
10
200
0.5
0.5
100
0.8
V
V
V
15
4
5
µs
ns
µs
ns
Note 2:
The charge pump on the MAX3171/MAX3173 can supply V+ and V- to the MAX3172/MAX3174. The V+ and V- input levels
vary with the mode of chipset operation as follows:
V.35/V.28 modes: +5.55V
≤
V+
≤
+6.50V, -6.50V
≤
V-
≤
-5.45V
Typical operation: V+ = +5.90V, V- = -5.80V
V.10/V.11 modes: +4.20V
≤
V+
≤
+5.0V, -4.60V
≤
V-
≤
-3.80V
Typical operation: V+ = +4.60V, V- = -4.20V
The MAX3171/MAX3173 are guaranteed to provide these V+/V- supply levels.
4
_______________________________________________________________________________________
+3.3V Multiprotocol Software-Selectable
Cable Terminators and Transceivers
Typical Operating Characteristics
(V
CC
= +3.3V (see Note 2 in
Electrical Characteristics
table), T
A
= +25°C, unless otherwise noted.)
V.28 60kbps TRANSMITTER
WAVEFORM (3kΩ/1000pF LOAD)
MAX3172-02
MAX3172/MAX3174
V.28 SLEW RATE
vs. LOAD CAPACITANCE
24
22
20
18
16
14
12
10
8
6
4
2
0
0
500
-SLEW
5V
0
-5V
2000
R
L
= 3kΩ
+SLEW
MAX3172-01
5V
0
T4IN
5V/div
SLEW RATE (V/µs)
T4OUT
5V/div
1000
1500
2500
3000
10µs/div
LOAD CAPACITANCE (pF)
V.10 RISE AND FALL TIMES
vs. LOAD CAPACITANCE
MAX3172-03
V.10 60kbps TRANSMITTER
WAVEFORM (450Ω/100pF)
MAX3172-04
2.5
FALL TIME
RISE AND FALL TIMES (µs)
2.0
5V
0
T4IN
5V/div
1.5
RISE TIME
1.0
5V
0
0.5
-5V
R
L
= 450Ω
0
0
500
1000
1500
2000
2500
3000
10µs/div
LOAD CAPACITANCE (pF)
T4OUT
5V/div
V.11/V.35 DIFFERENTIAL-MODE
IMPEDANCE vs. TEMPERATURE
DIFFERENTIAL-MODE IMPEDANCE (Ω)
DIFFERENTIAL-MODE IMPEDANCE (Ω)
109
108
107
106
105
104
103
102
101
100
-10
0
10
20
30
40
50
60
70
80
TEMPERATURE (°C)
V
CM
= -7V
V
CM
= +7V
V
CM
= 0
MAX3172-05
V.11/V.35 DIFFERENTIAL-MODE
IMPEDANCE vs. COMMON-MODE VOLTAGE
109
108
107
106
105
104
103
102
101
100
-7
-5
-3
-1
1
3
5
7
COMMON-MODE VOLTAGE (V)
MAX3172-06
110
110
_______________________________________________________________________________________
5
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