19-2217; Rev 1; 2/03
+5V, Fail-Safe, 20Mbps, Profibus RS-485/
RS-422 Transceivers
General Description
The MAX3460–MAX3464 are high-speed differential
bus transceivers for RS-485 and RS-422 communica-
tions. They are designed to meet TIA/EIA-422-B,
TIA/EIA-485-A, V.11, and X.27 standards. The trans-
ceiver complies with the Profibus specification provid-
ing +2.1V output level with a 54Ω load, 20Mbps data
rate, and output skew less than 2ns. Each part contains
one three-state differential line driver and one differen-
tial input line receiver. The devices operate from a +5V
supply and feature true fail-safe circuitry, which guaran-
tees a logic-high receiver output when the receiver
inputs are open or shorted. This enables all receiver
outputs on a terminated bus to output logic highs when
all transmitters are disabled.
All devices feature a 1/4 standard unit load receiver
input impedance that allows 128 transceivers on the
bus. Driver and receiver propagation delays are guar-
anteed under 20ns for multidrop, clock distribution
applications. Drivers are short-circuit current limited
and are protected against excessive power dissipation
by thermal shutdown circuitry. The driver and receiver
feature active-high and active-low enables, respective-
ly, that can be connected together externally to serve
as a direction control.
o
Guaranteed 20Mbps Data Rate
o
20ns Transmitter and Receiver Propagation Delay
o
2ns Transmitter and Receiver Skew
o
High Differential Driver Output Level (2.1V on 54Ω)
o
Hot-Swap Versions
o
1µA Shutdown Supply Current
o
Low Supply Current Requirements (2.5mA typ)
o
Allow Up to 128 Transceivers on the Bus
o
True Fail-Safe Receiver while Maintaining EIA/TIA-
485 Compatibility
o
Designed for Multipoint Transmissions on Long
or Noisy Bus Lines
o
Full Duplex and Half Duplex Versions Available
o
Phase Controls to Correct for Twisted-Pair
Reversal for 14-Pin Versions
o
Current-Limiting and Thermal Shutdown for
Driver Overload Protection
Features
o
Recommended for Profibus Applications
MAX3460–MAX3464
Applications
High-Speed RS-485 Communications
High-Speed RS-422 Communications
Level Translators
Industrial-Control Local Area Networks
Profibus Applications
PART
MAX3460CSD
MAX3460CPD
MAX3460ESD
MAX3460EPD
Ordering Information
TEMP RANGE
0°C to +70°C
0°C to +70°C
-40°C to +85°C
-40°C to +85°C
PIN-PACKAGE
14 SO
14 Plastic DIP
14 SO
14 Plastic DIP
Ordering Information continued at end of data sheet.
Pin Configurations appear at end of data sheet.
Selector Guide
PART
NUMBER
MAX3460
MAX3461
MAX3462
MAX3463
MAX3464
HALF/FULL
DUPLEX
Full
Full
Full
Half
Half
RECEIVER/
DRIVER
ENABLE
Yes
Yes
No
Yes
Yes
LOW-
POWER
SHUTDOWN
Yes
Yes
No
Yes
Yes
HOT SWAP
Yes
No
No
Yes
No
RECEIVER/
DRIVER PHASE
SELECT
Yes
Yes
No
No
No
INDEPENDENT
SHDN PIN
Yes
Yes
No
No
No
PIN COUNT
14
14
8
8
8
________________________________________________________________
Maxim Integrated Products
1
For pricing, delivery, and ordering information, please contact Maxim/Dallas Direct! at
1-888-629-4642, or visit Maxim’s website at www.maxim-ic.com.
+5V, Fail-Safe, 20Mbps, Profibus RS-485/
RS-422 Transceivers
MAX3460–MAX3464
ABSOLUTE MAXIMUM RATINGS
Supply Voltage (V
CC
) to GND ..................................-0.3V to +6V
Control Input Voltage (RE, DE, DI, SHDN, TXP, RXP)
to GND....................................................-0.3V to (V
CC
+ 0.3V)
Driver Output Voltage (Y, Z) to GND .........................-8V to +13V
Receiver Input Voltage (A, B) to GND.......................-8V to +13V
Differential Driver Output Voltage (Y - Z) ...............................±8V
Differential Receiver Input (A - B) ..........................................±8V
Receiver Output Voltage (RO) to GND.......-0.3V to (V
CC
+ 0.3V)
Output Driver Current (Y, Z) ...........................................±250mA
Continuous Power Dissipation (T
A
= +70°C)
8-Pin SO (derate 5.88mW/°C above +70°C)................471mW
8-Pin DIP (derate 9.09mW/°C above +70°C) ...............727mW
14-Pin SO (derate 8.33mW/°C above +70°C)..............667mW
14-Pin DIP (derate 10mW/°C above +70°C) ................800mW
Operating Temperature Range
MAX346_C__ ......................................................0°C to +70°C
MAX346_E__....................................................-40°C to +85°C
Junction Temperature ......................................................+150°C
Storage Temperature Range .............................-65°C to +150°C
Lead Temperature (soldering, 10s) .................................+300°C
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
= +5V ±5%, T
A
= T
MIN
to T
MAX
, unless otherwise noted. Typical values are at V
CC
= +5V and T
A
= +25°C.) (Note 1)
PARAMETER
Power-Supply Range
DRIVER
Differential Driver Output (no load)
Differential Driver Output
Change in Magnitude of
Differential Output Voltage
Driver Common-Mode Output
Voltage
Change in Magnitude of
Common-Mode Voltage
Input High Voltage
Input Low Voltage
Input Hysteresis
Output Leakage (Y and Z) Full
Duplex
Input Current
Pulldown Current
Driver Short-Circuit Output
Current (Note 3)
Driver Short-Circuit Foldback
Output Current (Note 3)
Thermal Shutdown Threshold
RECEIVER
Differential Input Capacitance
Input Current (A and B) Full
Duplex
Receiver Differential Threshold
Voltage
C
A, B
I
A, B
V
TH
DE = GND,
V
CC
= GND or 5.25V
-7V
≤
V
CM
≤
12V
V
IN
= +12V
V
IN
= -7V
-200
-200
-125
-50
8
250
pF
µA
mV
I
OSD
I
OSFD
V
OD
V
OD
∆V
OD
V
OC
∆V
OC
V
IH
V
IL
V
HYS
I
O
I
IN
Figure 5, R =
∞
Figure 5, R = 27Ω
Figure 5, R = 50Ω or 27Ω
(Note 2)
Figure 5, R = 50Ω or 27Ω
Figure 5, R = 50Ω or 27Ω
(Note 2)
DE, DI,
RE,
SHDN
DE, DI,
RE,
SHDN
DE, DI,
RE,
SHDN
DE = GND, V
CC
=
GND or +5.25V
DI,
RE,
DE, SHDN
RXP = TXP = V
CC
0
≤
V
OUT
≤
12V, output low
-7V
≤
V
OUT
≤
V
CC
, output high
(V
CC
- 1V)
≤
V
OUT
≤
12V, output low
-7V
≤
V
OUT
≤
1V, output high
140
-250
+25
-25
5
15
V
IN
= +12V
V
IN
= -7V
-100
±1
30
+250
50
+125
2.0
0.8
2.1
0.2
3
0.2
V
CC
V
V
V
V
V
V
V
mV
µA
µA
µA
mA
mA
°C
SYMBOL
V
CC
CONDITIONS
MIN
4.75
TYP
MAX
5.25
UNITS
V
2
_______________________________________________________________________________________
+5V, Fail-Safe, 20Mbps, Profibus RS-485/
RS-422 Transceivers
ELECTRICAL CHARACTERISTICS (continued)
(V
CC
= +5V ±5%, T
A
= T
MIN
to T
MAX
, unless otherwise noted. Typical values are at V
CC
= +5V and T
A
= +25°C.) (Note 1)
PARAMETER
Receiver Input Hysteresis
Receiver Output High Voltage
Receiver Output Low Voltage
Three-State Output Current at
Receiver
Receiver Input Resistance
Receiver Output Short-Circuit
Current
SUPPLY CURRENT
Normal Operation (static condition)
Supply Current in SHDN
SWITCHING CHARACTERISTICS
Driver Propagation Delay
Driver Differential Output Rise or
Fall Time
Driver Output Skew |t
PLH
- t
PHL
|
Maximum Data Rate
Driver Enable to Output High
Driver Enable to Output Low
Driver Disable Time from Low
Driver Disable Time from High
Receiver Propagation Delay
Receiver Output Skew |t
PLH
- t
PHL
|
Receiver Enable to Output Low
Receiver Enable to Output High
Receiver Disable Time from Low
Receiver Disable Time from High
t
ZH
t
ZL
t
LZ
t
HZ
t
PLH
t
PHL
t
SKEW
t
ZL
t
ZH
t
LZ
t
HZ
Figures 8 and 9, S2 closed, R
L
= 500Ω,
C
L
= 50pF
Figures 8 and 9, S1 closed, R
L
= 500Ω,
C
L
= 50pF
Figures 8 and 9, S1 closed, R
L
= 500Ω,
C
L
= 50pF
Figures 8 and 9, S2 closed, R
L
= 500Ω,
C
L
= 50pF
Figure 10, C
L
= 15pF (Note 4)
Figure 10, C
L
= 15pF, RXP = GND or
floating (Note 4)
Figures 8 and 11, R
L
= 1kΩ, C
L
= 15pF,
S1 closed (Note 4)
Figures 8 and 11, R
L
= 1kΩ, C
L
= 15pF,
S2 closed (Note 4)
Figures 8 and 11, R
L
= 1kΩ, C
L
= 15pF,
S1 closed (Note 4)
Figures 8 and 11, R
L
= 1kΩ, C
L
= 15pF,
S2 closed (Note 4)
t
PLH
t
PHL
t
R
t
F
t
SKEW
Figures 6 and 7, R
DIFF
= 54Ω,
C
L
= 50pF
Figures 6 and 7, R
DIFF
= 54Ω,
C
L
= 50pF
Figures 6 and 7, R
DIFF
= 54Ω,
C
L
= 50pF, TXP = GND or floating
20
100
100
100
100
20
2
100
100
100
100
20
20
2
ns
ns
ns
Mbps
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
I
Q
I
SHDN
No load, DI = V
CC
or DI = GND
DE = GND and
RE
= V
CC
, or SHDN = V
CC
2.5
1
4
10
mA
µA
SYMBOL
∆V
TH
V
OH
V
OL
I
OZR
R
IN
I
OSR
V
A
+ V
B
= 0
I
O
= -4mA, V
A
- V
B
= V
TH
I
O
= 4mA, V
B
- V
A
= V
TH
0
≤
V
O
≤
V
CC
-7V
≤
V
CM
≤
12V
0
≤
V
RO
≤
V
CC
48
±7
±95
V
CC
- 1.5
0.4
±1
CONDITIONS
MIN
TYP
20
MAX
UNITS
mV
V
V
µA
kΩ
mA
MAX3460–MAX3464
_______________________________________________________________________________________
3
+5V, Fail-Safe, 20Mbps, Profibus RS-485/
RS-422 Transceivers
MAX3460–MAX3464
ELECTRICAL CHARACTERISTICS (continued)
(V
CC
= +5V ±5%, T
A
= T
MIN
to T
MAX
, unless otherwise noted. Typical values are at V
CC
= +5V and T
A
= +25°C.) (Note 1)
PARAMETER
Time to Shutdown
Driver Enable from Shutdown to
Output High
Driver Enable from Shutdown to
Output Low
Receiver Enable from Shutdown to
Output High
Receiver Enable from Shutdown to
Output Low
SYMBOL
t
SHDN
t
ZH (SHDN)
t
ZL (SHDN)
t
ZH (SHDN)
t
ZL (SHDN)
(Note 5)
Figures 8 and 9, R
L
= 500Ω, C
L
= 50pF,
S2 closed (Note 5)
Figures 8 and 9, R
L
= 500Ω, C
L
= 50pF,
S1 closed (Note 5)
Figures 8 and 11, R
L
= 1kΩ, C
L
= 15pF,
S2 closed (Notes 4, 5)
Figures 8 and 11, R
L
= 1kΩ, C
L
= 15pF,
S1 closed (Notes 4, 5)
CONDITIONS
MIN
50
TYP
MAX
800
4
4
4
4
UNITS
ns
µs
µs
µs
µs
Note 1:
All currents into the device are positive; all currents out of the device are negative. All voltages are referenced to device
ground, unless otherwise noted.
Note 2:
∆V
OD
and
∆V
OC
are the changes in V
OD
and V
OC
, respectively, when the DI input changes state.
Note 3:
The short-circuit output current applies to peak current just prior to foldback-current limiting; the short-circuit foldback output
current applies during current limiting to allow a recovery from bus contention.
Note 4:
Capacitive load includes test probe and fixture capacitance.
Note 5:
Shutdown is enabled by bringing
RE
high and DE low or by bringing SHDN high. If the enable inputs are in this state for less
than 50ns, the device is guaranteed not to enter shutdown. If the enable inputs are in this state for at least 800ns, the device
is guaranteed to have entered shutdown.
Typical Operating Characteristics
(V
CC
= +5V, T
A
= +25°C, unless otherwise noted.)
NO LOAD SUPPLY CURRENT
vs. TEMPERATURE
MAX3460-64 toc01
OUTPUT CURRENT
vs. RECEIVER OUTPUT LOW VOLTAGE
MAX3460-64 toc02
OUTPUT CURRENT
vs. RECEIVER OUTPUT HIGH VOLTAGE
MAX3460-64 toc03
2.40
NO LOAD SUPPLY CURRENT (mA)
2.35
2.30
2.25
2.20
DE = GND
2.15
2.10
2.05
2.00
-40
-20
40
TEMPERATURE (°C)
0
20
60
80
DE = V
CC
60
50
OUTPUT CURRENT (mA)
40
30
20
10
0
0
35
30
OUTPUT CURRENT (mA)
25
20
15
10
5
0
0.5 1.0 1.5 2.0 2.5 3.0 3.5 4.0 4.5 5.0
OUTPUT LOW VOLTAGE (V)
0
1
2
3
4
5
OUTPUT HIGH VOLTAGE (V)
4
_______________________________________________________________________________________
+5V, Fail-Safe, 20Mbps, Profibus RS-485/
RS-422 Transceivers
Typical Operating Characteristics (continued)
(V
CC
= +5V, T
A
= +25°C, unless otherwise noted.)
MAX3460–MAX3464
SHUTDOWN SUPPLY CURRENT
vs. TEMPERATURE
MAX3460-64 toc04
RECEIVER OUTPUT LOW VOLTAGE
vs. TEMPERATURE
MAX3460-64 toc05
RECEIVER OUTPUT HIGH VOLTAGE
vs. TEMPERATURE
I
O
= -4mA
MAX3460-64 toc06
50
SHUTDOWN SUPPLY CURRENT (nA)
4.90
4.85
OUTPUT HIGH VOLTAGE (V)
4.80
4.75
4.70
4.65
RECEIVER OUTPUT LOW VOLTAGE (mV)
I
O
= 4mA
140
40
30
120
20
100
10
0
-40
-15
10
35
60
85
TEMPERATURE (°C)
80
-40
-15
10
35
60
85
TEMPERATURE (°C)
4.60
-40
-15
10
35
60
85
TEMPERATURE (°C)
RECEIVER PROPAGATION DELAY
vs. TEMPERATURE
MAX3460-64 toc07
DRIVER PROPAGATION DELAY
vs. TEMPERATURE
MAX3460-64 toc08
DRIVER DIFFERENTIAL OUTPUT VOLTAGE
vs. TEMPERATURE
R
DIFF
= 54Ω
MAX3460-64 toc09
11
12
4.0
R
DIFF
= 54Ω
C
L
= 50pF
PROPAGATION DELAY (ns)
9
OUTPUT VOLTAGE (V)
10
PROPAGATION DELAY (ns)
10
3.5
8
3.0
8
6
2.5
7
-40
-15
10
35
60
85
TEMPERATURE (°C)
4
-40
-15
10
35
60
85
TEMPERATURE (°C)
2.0
-40
-15
10
35
60
85
TEMPERATURE (°C)
DRIVER OUTPUT CURRENT
vs. DIFFERENTIAL OUTPUT VOLTAGE
MAX3460-64 toc10
OUTPUT CURRENT
vs. DRIVER OUTPUT LOW VOLTAGE
MAX3460-64 toc11
OUTPUT CURRENT
vs. DRIVER OUTPUT HIGH VOLTAGE
MAX3460-64 toc12
100
200
-160
160
OUTPUT CURRENT (mA)
OUTPUT CURRENT (mA)
10
120
OUTPUT CURRENT (mA)
-120
-80
80
1
40
-40
0.1
0
1
2
3
4
5
DIFFERENTIAL OUTPUT VOLTAGE (V)
0
0
3
6
9
12
OUTPUT LOW VOLTAGE (V)
0
-7
-5
-3
-1
1
3
5
OUTPUT HIGH VOLTAGE (V)
_______________________________________________________________________________________
5
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