Click here for production status of specific part numbers.
MAX3483E/MAX3485E/
MAX3486E/MAX3488E/
MAX3490E/MAX3491E
3.3V-Powered, ±15kV ESD-Protected,
12Mbps and Slew-Rate-Limited
True RS-485/RS-422 Transceivers
General Description
Features
Devices in the MAX3483E family (MAX3483E/MAX3485E/
MAX3486E/MAX3488E/MAX3490E/MAX3491E) are
±15kV ESD-protected, +3.3V, low-power transceivers for
RS-485 and RS-422 communications. Each device contains one driver and one receiver. The MAX3483E and
MAX3488E feature slew-rate-limited drivers that minimize
EMI and reduce reflections caused by improperly terminated cables, allowing error-free data transmission at
data rates up to 250kbps. The partially slew-rate-limited
MAX3486E transmits up to 2.5Mbps. The MAX3485E,
MAX3490E, and MAX3491E transmit at up to 12Mbps.
●● ESD Protection for RS-485 I/O Pins
• ±15kV—Human Body Model
• ±8kV—IEC 1000-4-2, Contact Discharge
• ±15kV—IEC 1000-4-2, Air-Gap Discharge
●● Operate from a Single +3.3V Supply—
No Charge Pump Required
●● Interoperable with +5V Logic
●● Guaranteed 12Mbps Data Rate
(MAX3485E/MAX3490E/MAX3491E)
●● Slew-Rate Limited for Errorless Data Transmission
(MAX3483E/MAX3488E)
All devices feature enhanced electrostatic discharge
(ESD) protection. All transmitter outputs and receiver
inputs are protected to ±15kV using IEC 1000-4-2 Air-Gap
Discharge, ±8kV using IEC 1000-4-2 Contact Discharge,
and ±15kV using the Human Body Model.
●● 2nA Low-Current Shutdown Mode
(MAX3483E/MAX3485E/MAX3486E/MAX3491E)
●● -7V to +12V Common-Mode Input Voltage Range
●● Full-Duplex and Half-Duplex Versions Available
Drivers are short-circuit current limited and are protected
against excessive power dissipation by thermal shutdown
circuitry that places the driver outputs into a high-impedance
state. The receiver input has a fail-safe feature that guarantees a logic-high output if both inputs are open circuit.
●● Industry-Standard 75176 Pinout
(MAX3483E/MAX3485E/MAX3486E)
●● Current-Limiting and Thermal Shutdown for
Driver Overload Protection
The MAX3488E, MAX3490E, and MAX3491E feature fullduplex communication, while the MAX3483E, MAX3485E,
and MAX3486E are designed for half-duplex communication.
Ordering Information
Applications
●●
●●
●●
●●
●●
Telecommunications
Industrial-Control Local Area Networks
Transceivers for EMI-Sensitive Applications
Integrated Services Digital Networks
Packet Switching
PART
TEMP. RANGE
MAX3483ECSA
0°C to+70°C
8 SO
PIN-PACKAGE
MAX3483ECPA
0°C to+70°C
8 Plastic DIP
MAX3483EESA
-40°C to+85°C
8 SO
MAX3483EEPA
-40°C to+85°C
8 Plastic DIP
Ordering Information continued at end of data sheet.
Selector Guide
PART
NUMBER
GUARANTEED
DATA RATE
(Mbps)
MAX3483E
0.25
SUPPLY
VOLTAGE
(V)
HALF/FULL
DUPLEX
SLEW-RATE
LIMITED
DRIVER/
RECEIVER
ENABLE
SHUTDOWN
CURRENT
(nA)
±15kV
ESD
PROTECTION
PIN
COUNT
Half
Yes
Yes
2
Yes
8
MAX3485E
12
Half
No
Yes
2
Yes
8
MAX3486E
2.5
Half
Yes
Yes
2
Yes
8
MAX3488E
0.25
Full
Yes
No
—
Yes
8
MAX3490E
12
Full
No
No
—
Yes
8
MAX3491E
12
Full
No
Yes
2
Yes
14
19-1474; Rev 1; 5/19
3.0 to 3.6
MAX3483E/MAX3485E/
MAX3486E/MAX3488E/
MAX3490E/MAX3491E
3.3V-Powered, ±15kV ESD-Protected,
12Mbps and Slew-Rate-Limited
True RS-485/RS-422 Transceivers
Absolute Maximum Ratings
Supply Voltage (VCC).............................................................+7V
Control Input Voltage (RE, DE)................................-0.3V to +7V
Driver Input Voltage (DI)...........................................-0.3V to +7V
Driver Output Voltage (A, B, Y, Z).......................-7.5V to +12.5V
Receiver Input Voltage (A, B)..............................-7.5V to +12.5V
Receiver Output Voltage (RO).................. -0.3V to (VCC + 0.3V)
Continuous Power Dissipation (TA = +70°C)
8-Pin SO (derate 5.88mW/°C above +70°C)................471mW
8-Pin Plastic DIP (derate 9.09mW/°C above +70°C)...727mW
14-Pin SO (derate 8.33mW/°C above +70°C).................667mW
14-Pin Plastic DIP (derate 10mW/°C above +70°C)........800mW
Operating Temperature Ranges
MAX34_ _ EC_ _.................................................0°C to +70°C
MAX34_ _ EE_ _............................................. -40°C to +85°C
Junction Temperature.......................................................+150°C
Storage Temperature Range............................. -65°C to +150°C
Lead Temperature (soldering, 10sec).............................. +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.
Package Information
TDFN-14
PACKAGE CODE
S14+1
Outline Number
21-0041
Land Pattern Number
90-0112
Thermal Resistance, Single-Layer Board:
Junction to Ambient (θJA)
120°C/W
Junction to Case (θJC)
37°C/W
Thermal Resistance, Four-Layer Board:
Junction to Ambient (θJA)
84°C/W
Junction to Case (θJC)
34°C/W
For the latest package outline information and land patterns (footprints), go to www.maximintegrated.com/packages. Note that
a “+”, “#”, or “-” in the package code indicates RoHS status only. Package drawings may show a different suffix character, but the
drawing pertains to the package regardless of RoHS status.
Package thermal resistances were obtained using the method described in JEDEC specification JESD51-7, using a four-layer board.
For detailed information on package thermal considerations, refer to www.maximintegrated.com/thermal-tutorial.
www.maximintegrated.com
Maxim Integrated │ 2
MAX3483E/MAX3485E/
MAX3486E/MAX3488E/
MAX3490E/MAX3491E
3.3V-Powered, ±15kV ESD-Protected,
12Mbps and Slew-Rate-Limited
True RS-485/RS-422 Transceivers
DC Electrical Characteristics
(VCC = +3.3V ±0.3V, TA = TMIN to TMAX, unless otherwise noted. Typical values are at TA = +25°C.)
PARAMETER
Differential Driver Output
SYMBOL
VOD
CONDITIONS
MIN
RL = 100Ω (RS-422), Figure 4
2.0
RL = 54Ω (RS-485), Figure 4
1.5
RL = 60Ω (RS-485), VCC = 3.3V, Figure 5
1.5
TYP
MAX
UNITS
V
Change in Magnitude of Driver
Differential Output Voltage for
Complementary Output States
(Note 1)
∆VOD
RL = 54Ω or 100Ω, Figure 4
0.2
V
Driver Common-Mode Output
Voltage
VOC
RL = 54Ω or 100Ω, Figure 4
3
V
∆VOC
RL = 54Ω or 100Ω, Figure 4
0.2
V
Change in Magnitude of
Common-Mode Output Voltage
(Note 1)
Input High Voltage
VIH
DE, DI, RE
Input Low Voltage
VIL
DE, DI, RE
Logic Input Current
IIN1
DE, DI, RE
Input Current (A, B)
IIN2
2.0
V
0.8
V
±2
μA
DE = 0V,
VCC = 0V or 3.6V
VIN = 12V
1.0
VIN = -7V
-0.8
Output Leakage (Y, Z)
IO
DE = 0V, RE = 0V,
VCC = 0V or 3.6V, MAX3491E
VOUT = 12V
20
VOUT = -7V
-20
Output Leakage (Y, Z)
in Shutdown Mode
IO
DE = 0V, RE = VCC,
VCC = 0V or 3.6V, MAX3491E
VOUT = 12V
1
VOUT = -7V
-1
Receiver Differential Threshold
Voltage
VTH
-7V ≤ VCM ≤ 12V
-0.2
0.2
mA
μA
μA
V
Receiver Input Hysteresis
∆VTH
VCM = 0V
Receiver Output High Voltage
VOH
IOUT = -1.5mA, VID = 200mV, Figure 6
Receiver Output Low Voltage
VOL
IOUT = 2.5mA, VID = 200mV, Figure 6
0.4
V
Three-State (High Impedance)
Output Current at Receiver
IOZR
VCC = 3.6V, 0V ≤ VOUT ≤ VCC
±1
μA
Receiver Input Resistance
RIN
-7V ≤ VCM ≤ 12V
Supply Voltage Range
VCC
www.maximintegrated.com
50
mV
VCC - 0.4
V
12
3.0
kΩ
3.6
V
Maxim Integrated │ 3
MAX3483E/MAX3485E/
MAX3486E/MAX3488E/
MAX3490E/MAX3491E
3.3V-Powered, ±15kV ESD-Protected,
12Mbps and Slew-Rate-Limited
True RS-485/RS-422 Transceivers
DC Electrical Characteristics (continued)
(VCC = +3.3V ±0.3V, TA = TMIN to TMAX, unless otherwise noted. Typical values are at TA = +25°C)
PARAMETER
Supply Current
SYMBOL
ICC
Supply Current in Shutdown Mode
ISHDN
Driver Short-Circuit Output
Current
IOSD
Receiver Short-Circuit Output
Current
IOSR
ESD Protection for Y, Z, A, B
CONDITIONS
No load,
DI = 0 or VCC
MIN
DE = VCC, RE = 0 or VCC
DE = 0V, RE = 0
DE = 0, RE = VCC, DI = VCC or 0
TYP
MAX
1.1
2.2
0.95
1.9
0.002
VOUT = -7V
1
-250
VOUT = 12V
250
0 ≤ VRO ≤ VCC
±8
±60
IEC 1000-4-2 Air Discharge
±15
IEC 1000-4-2 Contact Discharge (MAX3483E,
MAX3485E, MAX3486E, MAX3491E)
±8
IEC 1000-4-2 Contact Discharge (MAX3490E,
MAX3488E)*
±6
Human Body Model
±15
UNITS
mA
µA
mA
mA
kV
*MAX3488E and MAX3491E will be compliant to ±8kV per IEC 1000-4-2 Contact Discharge by September 1999.
Driver Switching Characteristics—MAX3485E/MAX3490E/MAX3491E
(VCC = +3.3V, TA = +25°C.)
PARAMETER
SYMBOL
CONDITIONS
Maximum Data Rate
MIN
TYP
12
15
MAX
UNITS
Mbps
Driver Differential Output Delay
tDD
RL = 60Ω, Figure 7
1
22
35
ns
Driver Differential Output Transition Time
tTD
RL = 60Ω, Figure 7
3
11
25
ns
Driver Propagation Delay, Low-to-High Level
tPLH
RL = 27Ω, Figure 8
7
23
35
ns
Driver Propagation Delay, High-to-Low Level
tPHL
RL = 27Ω, Figure 8
7
|tPLH - tPHL| Driver Propagation Delay Skew (Note 2)
tPDS
RL = 27Ω, Figure 8
23
35
ns
-1.4
±8
ns
DRIVER-OUTPUT ENABLE/DISABLE TIMES (MAX3485E/MAX3491E only)
Driver-Output Enable Time to Low Level
tPZL
RL = 110Ω, Figure 10
42
90
ns
Driver-Output Enable Time to High Level
tPZH
RL = 110Ω, Figure 9
42
90
ns
Driver-Output Disable Time from High Level
tPHZ
RL = 110Ω, Figure 9
35
80
ns
Driver-Output Disable Time from Low Level
tPLZ
RL = 110Ω, Figure 10
35
80
ns
Driver-Output Enable Time from Shutdown to Low Level
tPSL
RL = 110Ω, Figure 10
650
900
ns
Driver-Output Enable Time from Shutdown to High Level
tPSH
RL = 110Ω, Figure 9
650
900
ns
www.maximintegrated.com
Maxim Integrated │ 4
MAX3483E/MAX3485E/
MAX3486E/MAX3488E/
MAX3490E/MAX3491E
3.3V-Powered, ±15kV ESD-Protected,
12Mbps and Slew-Rate-Limited
True RS-485/RS-422 Transceivers
Driver Switching Characteristics—MAX3486E
(VCC = +3.3V, TA = +25°C.)
PARAMETER
SYMBOL
CONDITIONS
Maximum Data Rate
MIN
TYP
MAX
2.5
Driver Differential Output Delay
UNITS
Mbps
tDD
RL = 60Ω, Figure 7
20
42
70
ns
Driver Differential Output Transition Time
tTD
RL = 60Ω, Figure 7
15
28
60
ns
Driver Propagation Delay, Low-to-High Level
tPLH
RL = 27Ω, Figure 8
20
42
75
ns
Driver Propagation Delay, High-to-Low Level
tPHL
RL = 27Ω, Figure 8
20
42
75
ns
|tPLH - tPHL| Driver Propagation Delay Skew (Note 2)
tPDS
RL = 27Ω, Figure 8
-6
±12
ns
DRIVER-OUTPUT ENABLE/DISABLE TIMES
Driver Output Enable Time to Low Level
tPZL
RL = 110Ω, Figure 10
52
100
ns
Driver Output Enable Time to High Level
tPZH
RL = 110Ω, Figure 9
52
100
ns
Driver Output Disable Time from High Level
tPHZ
RL = 110Ω, Figure 9
40
80
ns
Driver Output Disable Time from Low Level
tPLZ
RL = 110Ω, Figure 10
40
80
ns
Driver Output Enable Time from Shutdown to Low Level
tPSL
RL = 110Ω, Figure 10
700
1000
ns
Driver Output Enable Time from Shutdown to High Level
tPSH
RL = 110Ω, Figure 9
700
1000
ns
TYP
MAX
UNITS
Driver Switching Characteristics—MAX3483E/MAX3488E
(VCC = +3.3V, TA = +25°C)
PARAMETER
SYMBOL
CONDITIONS
Maximum Data Rate
MIN
250
kbps
Driver Differential Output Delay
tDD
RL = 60Ω, Figure 7
600
900
1400
ns
Driver Differential Output Transition Time
tTD
RL = 60Ω, Figure 7
400
740
1200
ns
Driver Propagation Delay, Low-to-High Level
tPLH
RL = 27Ω, Figure 8
700
930
1500
ns
Driver Propagation Delay, High-to-Low Level
tPHL
RL = 27Ω, Figure 8
700
930
1500
ns
|tPLH - tPHL| Driver Propagation Delay Skew (Note 2)
tPDS
RL = 27Ω, Figure 8
±50
ns
DRIVER-OUTPUT ENABLE/DISABLE TIMES (MAX3483E only)
Driver-Output Enable Time to Low Level
tPZL
RL = 110Ω, Figure 10
900
1300
ns
Driver-Output Enable Time to High Level
tPZH
RL = 110Ω, Figure 9
600
800
ns
Driver-Output Disable Time from High Level
tPHZ
RL = 110Ω, Figure 9
50
80
ns
Driver-Output Disable Time from Low Level
tPLZ
RL = 110Ω, Figure 10
50
80
ns
Driver-Output Enable Time from Shutdown to Low Level
tPSL
RL = 110Ω, Figure 10
1.9
2.7
µs
Driver-Output Enable Time from Shutdown to High Level
tPSH
RL = 110Ω, Figure 9
2.2
3.0
µs
www.maximintegrated.com
Maxim Integrated │ 5
MAX3483E/MAX3485E/
MAX3486E/MAX3488E/
MAX3490E/MAX3491E
3.3V-Powered, ±15kV ESD-Protected,
12Mbps and Slew-Rate-Limited
True RS-485/RS-422 Transceivers
Receiver Switching Characteristics
(VCC = +3.3V, TA = +25°C)
PARAMETER
SYMBOL
CONDITIONS
MIN
TYP
MAX
UNITS
Time to Shutdown
tSHDN
MAX3483E/MAX3485E/MAX3486E/MAX3491E
only (Note 3)
80
190
300
ns
Receiver Propagation Delay,
Low-to-High Level
tRPLH
VID = 0 to 3.0, CL = 15pF, Figure 11
25
62
90
MAX3483E/MAX3488E
25
75
120
Receiver Propagation Delay,
High-to-Low Level
tRPHL
VID = 0 to 3.0, CL = 15pF, Figure 11
25
62
90
MAX3483E/MAX3488E
25
75
120
|tPLH - tPHL| Receiver
Propagation Delay Skew
tRPDS
VID = 0 to 3.0, CL = 15pF, Figure 11
6
±10
MAX3483E/MAX3488E
12
±20
Receiver Output Enable Time
to Low Level
tPRZL
CL = 15pF, Figure 12,
MAX3483E/85E/86E/91E only
25
50
ns
Receiver Output Enable Time
to High Level
tPRZH
CL = 15pF, Figure 12,
MAX3483E/85E/86E/91E only
25
50
ns
Receiver Output Disable
Time from High Level
tPRHZ
CL = 15pF, Figure 12,
MAX3483E/85E/86E/91E only
25
45
ns
Receiver Output Disable
Time from Low Level
tPRLZ
CL = 15pF, Figure 12,
MAX3483E/85E/86E/91E only
25
45
ns
Receiver Output Enable Time
from Shutdown to Low Level
tPRSL
CL = 15pF, Figure 12,
MAX3483E/85E/86E/91E only
720
1400
ns
Receiver Output Enable Time
from Shutdown to High Level
tPRSH
CL = 15pF, Figure 12,
MAX3483E/85E/86E/91E only
720
1400
ns
ns
ns
ns
Note 1: ∆VOD and ∆VOC are the changes in VOD and VOC, respectively, when the DI input changes state.
Note 2: Measured on |tPLH (Y) - tPHL (Y)| and |tPLH (Z) - tPHL (Z)|.
Note 3: The transceivers are put into shutdown by bringing RE high and DE low. If the inputs are in this state for less than 80ns,
the parts are guaranteed not to enter shutdown. If the inputs are in this state for at least 300ns, the parts are guaranteed to
have entered shutdown. See Low-Power Shutdown Mode section.
www.maximintegrated.com
Maxim Integrated │ 6
MAX3483E/MAX3485E/
MAX3486E/MAX3488E/
MAX3490E/MAX3491E
3.3V-Powered, ±15kV ESD-Protected,
12Mbps and Slew-Rate-Limited
True RS-485/RS-422 Transceivers
Typical Operating Characteristics
(VCC = +3.3V, TA = +25°C, unless otherwise noted.)
OUTPUT CURRENT vs.
RECEIVER OUTPUT LOW VOLTAGE
TOC01
25
OUTPUT CURRENT vs.
RECEIVER OUTPUT HIGH VOLTAGE
RECEIVER OUTPUT HIGH VOLTAGE
vs. TEMPERATURE
TOC02
-20
15
10
-16
OUTPUT HIGH VOLTAGE (V)
OUTPUT CURRENT (mA)
OUTPUT CURRENT (mA)
-18
20
-14
-12
-10
-8
-6
-4
5
0.5
1.0
1.5
2.0
2.5
0
3.5
3.15
3.10
0
0.5
1.0
1.5
2.0
2.5
3.0
3.00
3.5
-40
-20
0
20
40
60
80
TEMPERATURE (°C)
RECEIVER OUTPUT LOW VOLTAGE
vs. TEMPERATURE
DRIVER OUTPUT CURRENT vs.
DIFFERENTIAL OUTPUT VOLTAGE
DRIVER DIFFERENTIAL OUTPUT
VOLTAGE vs.TEMPERATURE
TOC04
TOC05
100
IRO = 2.5mA
2.6
90
OUTPUT CURRENT (mA)
0.6
0.5
0.4
0.3
0.2
80
70
60
50
40
30
20
0.1
10
-40
3.20
OUTPUT HIGH VOLTAGE (V)
0.7
0
3.25
OUTPUT LOW VOLTAGE (V)
0.8
OUTPUT LOW VOLTAGE (V)
3.0
DIFFERENTIAL OUTPUT VOLTAGE (V)
0
IRO = 1.5mA
3.05
-2
0
TOC03
3.30
-20
0
20
40
60
80
0
100
0
TEMPERATURE (°C)
0.5
1.0
1.5
2.0
2.5
3.0
DIFFERENTIAL OUTPUT VOLTAGE (V)
OUTPUT CURRENT vs.
DRIVER OUTPUT LOW VOLTAGE
175
TOC07
100
75
50
2.5
2.4
2.3
2.2
2.1
2.0
1.9
1.8
1.7
1.6
-40
-20
0
20
40
60
80
100
TEMPERATURE (°C)
TOC08
-100
OUTPUT CURRENT (mA)
OUTPUT CURRENT (mA)
125
TOC06
R = 54Ω
OUTPUT CURRENT vs.
DRIVER OUTPUT HIGH VOLTAGE
150
-80
-60
-40
-20
25
0
3.5
100
0
2
4
6
8
OUTPUT LOW VOLTAGE (V)
www.maximintegrated.com
10
12
0
-7 -6 -5 -4 -3 -2 -1 0 1 2 3
OUTPUT HIGH VOLTAGE (V)
4
5
Maxim Integrated │ 7
MAX3483E/MAX3485E/
MAX3486E/MAX3488E/
MAX3490E/MAX3491E
3.3V-Powered, ±15kV ESD-Protected,
12Mbps and Slew-Rate-Limited
True RS-485/RS-422 Transceivers
Typical Operating Characteristics (continued)
(VCC = +3.3V, TA = +25°C, unless otherwise noted.)
SUPPLY CURRENT
vs. TEMPERATURE
TOC09
1.2
90
1.1
DE = VCC, RE = X
1.0
DE = 0, RE = 0
0.9
TOC10
100
X = DON’T CARE
SHUTDOWN CURRENT (nA)
SUPPLY CURRENT (mA)
SHUTDOWN CURRENT
vs. TEMPERATURE
0.8
80
70
60
50
40
30
20
10
0.7
-40
-20
0
20
40
60
80
0
100
-40
-20
0
20
40
60
80
100
TEMPERATURE (°C)
TEMPERATURE (°C)
Pin Description
PIN
MAX3483E
MAX3485E
MAX3486E
MAX3488E
MAX3490E
MAX3491E
1
2
2
—
NAME
FUNCTION
2
RO
Receiver Output. If A > B by 200mV, RO will be high; if A < B by 200mV, RO
will be low.
3
RE
Receiver Output Enable. RO is enabled when RE is low; RO is high
impedance when RE is high. If RE is high and DE is low, the device will
enter a low-power shutdown mode.
3
—
4
DE
Driver Output Enable. The driver outputs are enabled by bringing DE high.
They are high impedance when DE is low. If RE is high and DE is low, the
device will enter a low-power shutdown mode. If the driver outputs are
enabled, the parts function as line drivers. While they are high impedance,
they function as line receivers if RE is low.
4
3
5
DI
Driver Input. A low on DI forces output Y low and output Z high. Similarly, a
high on DI forces output Y high and output Z low.
5
4
6, 7
GND
Ground
—
5
9
Y
Noninverting Driver Output
—
6
10
Z
Inverting Driver Output
6
—
—
A
Noninverting Receiver Input and Noninverting Driver Output
—
8
12
A
Noninverting Receiver Input
7
—
—
B
Inverting Receiver Input and Inverting Driver Output
Inverting Receiver Input
—
7
11
B
8
1
13, 14
VCC
Positive Supply: 3.0V ≤ VCC ≤ 3.6V. Do not operate device with VCC > 3.6V
—
—
1, 8
N.C.
No Connection. Not internally connected.
www.maximintegrated.com
Maxim Integrated │ 8
MAX3483E/MAX3485E/
MAX3486E/MAX3488E/
MAX3490E/MAX3491E
3.3V-Powered, ±15kV ESD-Protected,
12Mbps and Slew-Rate-Limited
True RS-485/RS-422 Transceivers
TOP VIEW
R
1
RO
RO
1
8
VCC
RE 2
7
B
RE 2
DE 3
6
A
DE 3
5
GND
DI 4
D
DI 4
R
8 VCC
7 B
Rt
6
A
5 GND
D
MAX3483E
MAX3485E
MAX3486E
DE
Rt
D
B
A
DI
RO
R
RE
SO/DIP
NOTE: PIN LABELS Y AND Z ON TIMING, TEST, AND WAVEFORM DIAGRAMS REFER TO PINS A AND B WHEN DE IS HIGH.
Figure 1. MAX3483E/MAX3485E/MAX3486E Pin Configuration and Typical Operating Circuit
TOP VIEW
VCC
8
A
RO 2
7
B
DI 3
6
Z
5
Y
VCC 1
GND 4
R
D
DI
RO
3
5 Y
D
Rt
6 Z
8 A
2
VCC
MAX3488E
MAX3490E
1
R
7
R
RO
Rt
D
DI
B
SO/DIP
4
GND
GND
Figure 2. MAX3488E/MAX3490E Pin Configuration and Typical Operating Circuit
TOP VIEW
DE
4
N.C.
1
RO
2
RE
3
12 A
DE
4
11 B
DI
5
10 Z
GND
6
GND
7
VCC
13, 14
14 V CC
R
D
SO/DIP
13 V CC
9
Y
8
N.C.
DI
RO
N.C.
5
9
D
10
12
2
R
11
1, 8
3
VCC RE
MAX3491E
Y
Rt
R
RO
Z
A
Rt
D
DI
B
6, 7
RE GND
GND
DE
Figure 3. MAX3491E Pin Configuration and Typical Operating Circuit
www.maximintegrated.com
Maxim Integrated │ 9
MAX3483E/MAX3485E/
MAX3486E/MAX3488E/
MAX3490E/MAX3491E
3.3V-Powered, ±15kV ESD-Protected,
12Mbps and Slew-Rate-Limited
True RS-485/RS-422 Transceivers
375Ω
RL
2
VOD
D
D
RL
VCC
VCM =
-7V to +12V
RL
VOD
VOC
2
VCC
Figure 4. Driver VOD and VOC
375Ω
Figure 5. Driver VOD with Varying Common-Mode Voltage
VID
R
0V
VOL
IOL
(+)
VOH
IOH
(-)
Figure 6. Receiver VOH and VOL
3V
IN
1.5V
1.5V
CL
D
GENERATOR
(NOTE 4)
0V
RL =
60Ω
OUT
tDO
50Ω
VCC
OUT
CL
CL = 15pF (NOTE 5)
50%
10%
tTD
tDO
90%
90%
≈ 2.0V
50%
10%
≈ -2.0V
tTD
Figure 7. Driver Differential Output Delay and Transition Times
www.maximintegrated.com
Maxim Integrated │ 10
MAX3483E/MAX3485E/
MAX3486E/MAX3488E/
MAX3490E/MAX3491E
3.3V-Powered, ±15kV ESD-Protected,
12Mbps and Slew-Rate-Limited
True RS-485/RS-422 Transceivers
3V
VOM
IN
1.5V
1.5V
RL = 27Ω
0V
S1
GENERATOR
(NOTE 4)
tPLH
OUT
D
50Ω
CL = 15pF
(NOTE 5)
VCC
VOM =
VOH + VOL
2
tPHL
VOH
Y
OUT
VOM
VOM
VOL
tPHL
≈ 1.5V
tPLH
VOH
Z
OUT
VOM
VOM
VOL
Figure 8. Driver Propagation Times
3V
S1
0V OR 3V
GENERATOR
(NOTE 4)
OUT
D
IN
0V
RL = 110Ω
CL = 50pF
(NOTE 5)
1.5V
1.5V
tPZH
tPHZ
50Ω
OUT
VOM =
VOH + VOL
2
0.25V
VOM
≈ 1.5V
VOH
0V
Figure 9. Driver Enable and Disable Times (tPZH, tPSH, tPHZ)
VCC
S1
0V OR 3V
3V
RL = 110Ω
IN
1.5V
1.5V
0V
OUT
D
tPSL
GENERATOR
(NOTE 4)
CL = 50pF
(NOTE 5)
50Ω
tPLZ
VCC
OUT
VOM
0.25V
VOL
Figure 10. Driver Enable and Disable Times (tPZL, tPSL, tPLZ)
www.maximintegrated.com
Maxim Integrated │ 11
MAX3483E/MAX3485E/
MAX3486E/MAX3488E/
MAX3490E/MAX3491E
VID
GENERATOR
(NOTE 4)
3.3V-Powered, ±15kV ESD-Protected,
12Mbps and Slew-Rate-Limited
True RS-485/RS-422 Transceivers
3.0V
OUT
R
IN
50Ω
CL = 15pF
(NOTE 5)
1.5V
1.5V
0V
tRPLH
tRPHL
VCC
1.5V
VOM =
0V
VOM
OUT
VCC
2
VOM
0V
Figure 11. Receiver Propagation Delay
S1
S3
1.5V
-1.5V
VID
GENERATOR
(NOTE 4)
R
50Ω
1.5V
0V
tPRZH
tPRSH
OUT
S2
CL
(NOTE 5)
3V
IN
VCC
1k
S1 OPEN
S2 CLOSED
S3 = 1.5V
3V
IN
1.5V
0V
tPRZL
tPRSL
VOH
OUT
1.5V
IN
1.5V
0V
VCC
1.5V
0V
3V
S1 CLOSED
S2 OPEN
S3 = -1.5V
VOL
S1 OPEN
S2 CLOSED
S3 = 1.5V
3V
IN
1.5V
0V
S1 CLOSED
S2 OPEN
S3 = -1.5V
tPRHZ
OUT 0.25V
tPRLZ
VOH
OUT
0V
VCC
0.25V
VOL
Figure 12. Receiver Enable and Disable Times
Note 4: The input pulse is supplied by a generator with the following characteristics: f = 250kHz, 50% duty cycle, tr ≤ 6.0ns, ZO = 50Ω.
Note 5: CL includes probe and stray capacitance.
www.maximintegrated.com
Maxim Integrated │ 12
MAX3483E/MAX3485E/
MAX3486E/MAX3488E/
MAX3490E/MAX3491E
3.3V-Powered, ±15kV ESD-Protected,
12Mbps and Slew-Rate-Limited
True RS-485/RS-422 Transceivers
Function Tables
Applications Information
Devices with Receiver/Driver Enable
(MAX3483E/MAX3485E/MAX3486E/MAX3491E)
Table 1. Transmitting
RE
INPUTS
OUTPUTS
MODE
DE
DI
B*
A*
X
1
1
0
1
Normal
X
1
0
1
0
Normal
0
0
X
High-Z
High-Z
Normal
1
0
X
High-Z
High-Z
Shutdown
* B and A outputs are Z and Y, respectively, for full-duplex part
(MAX3491E).
X = Don’t care; High-Z = High impedance
Table 2. Receiving
INPUTS
OUTPUTS
MODE
RE
DE
A, B
RO
0
0*
≥ +0.2V
1
Normal
0
0*
≤ -0.2V
0
Normal
0
0*
Inputs Open
1
Normal
1
0
X
High-Z
Shutdown
* DE is a “don’t care” (x) for the full-duplex part (MAX3491E).
X = Don’t care; High-Z = High impedance
Devices without Receiver/Driver Enable
(MAX3488E/MAX3490E)
Table 3. Transmitting
INPUT
Table 4. Receiving
INPUTS
OUTPUT
DI
Z
OUTPUTS
Y
A, B
RO
1
0
1
≥ +0.2V
1
0
1
0
≤ -0.2V
0
Inputs Open
1
The MAX3483E/MAX3485E/MAX3486E/MAX3488E/
MAX3490E/MAX3491E are low-power transceivers for
RS-485 and RS-422 communications. The MAX3483E
and MAX3488E can transmit and receive at data rates
up to 250kbps, the MAX3486E at up to 2.5Mbps, and the
MAX3485E/MAX3490E/MAX3491E at up to 12Mbps. The
MAX3488E/MAX3490E/MAX3491E are full-duplex transceivers, while the MAX3483E/MAX3485E/MAX3486E
are half-duplex. Driver Enable (DE) and Receiver Enable
(RE) pins are included on the MAX3483E/MAX3485E/
MAX3486E/MAX3491E. When disabled, the driver and
receiver outputs are high impedance.
Reduced EMI and Reflections
(MAX3483E/MAX3486E/MAX3488E)
The MAX3483E/MAX3488E are slew-rate limited, minimizing EMI and reducing reflections caused by improperly terminated cables. Figure 13 shows the driver output
waveform of a MAX3485E/MAX3490E/MAX3491E transmitting a 125kHz signal, as well as the Fourier analysis
of that waveform. High-frequency harmonics with large
amplitudes are evident. Figure 14 shows the same
information, but for the slew-rate-limited MAX3483E/
MAX3488E transmitting the same signal. The high-frequency harmonics have much lower amplitudes, and the
potential for EMI is significantly reduced.
Low-Power Shutdown Mode
(MAX3483E/MAX3485E/MAX3486E/MAX3491E)
A low-power shutdown mode is initiated by bringing both
RE high and DE low. The devices will not shut down
unless both the driver and receiver are disabled (high
impedance). In shutdown, the devices typically draw only
2nA of supply current.
For these devices, the tPSH and tPSL enable times
assume the part was in the low-power shutdown mode;
the tPZH and tPZL enable times assume the receiver or
driver was disabled, but the part was not shut down.
10dB/div
10dB/div
0
500kHz/div
5MHz
Figure 13. Driver Output Waveform and FFT Plot of MAX3485E/
MAX3490E/MAX3491E Transmitting a 125kHz Signal
www.maximintegrated.com
0
500kHz/div
5MHz
Figure 14. Driver Output Waveform and FFT Plot of
MAX3483E/ MAX3488E Transmitting a 125kHz Signal
Maxim Integrated │ 13
MAX3483E/MAX3485E/
MAX3486E/MAX3488E/
MAX3490E/MAX3491E
3.3V-Powered, ±15kV ESD-Protected,
12Mbps and Slew-Rate-Limited
True RS-485/RS-422 Transceivers
B
1V/div
DI
2V/div
A
1V/div
Z
1V/div
RO
2V/div
Y
1V/div
20ns/div
20ns/div
Figure 15. MAX3485E/MAX3490E/MAX3491E Driver
Propagation Delay
Figure 16. MAX3485E/MAX3490E/MAX3491E Receiver
Propagation Delay Driven by External RS-485 Device
B
1V/div
DI
2V/div
A
1V/div
Z
1V/div
Y
1V/div
RO
2V/div
1µs/div
1µs/div
Figure 17. MAX3483E/MAX3488E Driver Propagation Delay
Figure 18. MAX3483E/MAX3488E Receiver Propagation Delay
DI
5V/div
DI
5V/div
VY - VZ
2V/div
VY - VZ
2V/div
RO
5V/div
RO
5V/div
2µs/div
Figure 19. MAX3483E/MAX3488E System Differential Voltage
at 125kHz Driving 4000 Feet of Cable
www.maximintegrated.com
2µs/div
Figure 20. MAX3485E/MAX3490E/MAX3491E System
Differential Voltage at 125kHz Driving 4000 Feet of Cable
Maxim Integrated │ 14
MAX3483E/MAX3485E/
MAX3486E/MAX3488E/
MAX3490E/MAX3491E
3.3V-Powered, ±15kV ESD-Protected,
12Mbps and Slew-Rate-Limited
True RS-485/RS-422 Transceivers
Driver Output Protection
Excessive output current and power dissipation caused
by faults or by bus contention are prevented by two
mechanisms. A foldback current limit on the output stage
provides immediate protection against short circuits over
the whole common-mode voltage range (see Typical
Operating Characteristics). In addition, a thermal shutdown circuit forces the driver outputs into a high-impedance state if the die temperature rises excessively.
Propagation Delay
Figures 15–18 show the typical propagation delays. Skew
time is simply the difference between the low-to-high and
high-to-low propagation delay. Small driver/receiver skew
times help maintain a symmetrical mark-space ratio (50%
duty cycle).
The receiver skew time, |tPRLH - tPRHL|, is under 10ns
20ns for the MAX3483E/MAX3488E). The driver skew
times are 8ns for the MAX3485E/MAX3490E/MAX3491E,
12ns for the MAX3486E, and typically under 50ns for the
MAX3483E/MAX3488E.
Line Length vs. Data Rate
The RS-485/RS-422 standard covers line lengths up to
4000 feet. For line lengths greater than 4000 feet, see
Figure 21 for an example of a line repeater.
Figures 19 and 20 show the system differential voltage
for parts driving 4000 feet of 26AWG twisted-pair wire at
125kHz into 120Ω loads.
For faster data rate transmission, please consult the factory.
A
RO
RE
R
B
DATA IN
DE
DI
Z
D
Y
120Ω
DATA OUT
NOTE: RE AND DE ON MAX3491 ONLY.
Figure 21. Line Repeater for MAX3488E/MAX3490E/MAX3491E
www.maximintegrated.com
As with all Maxim devices, ESD-protection structures are
incorporated on all pins to protect against electrostatic
discharges encountered during handling and assembly.
The driver outputs and receiver inputs of the MAX3483E
family of devices have extra protection against static
electricity. Maxim’s engineers have developed state-ofthe-art structures to protect these pins against ESD of
±15kV without damage. The ESD structures withstand
high ESD in all states: normal operation, shutdown, and
powered down. After an ESD event, Maxim’s E versions
keep working without latchup or damage.
ESD protection can be tested in various ways; the transmitter outputs and receiver inputs of this product family
are characterized for protection to the following limits:
1) ±15kV using the Human Body Model
2) ±8kV using the Contact-Discharge method specified
in IEC 1000-4-2
3) ±15kV using IEC 1000-4-2’s Air-Gap method.
ESD Test Conditions
ESD performance depends on a variety of conditions.
Contact Maxim for a reliability report that documents test
setup, test methodology, and test results.
Human Body Model
Figure 22a shows the Human Body Model and Figure
22b shows the current waveform it generates when discharged into a low impedance. This model consists of a
100pF capacitor charged to the ESD voltage of interest,
which is then discharged into the test device through a
1.5kΩ resistor.
IEC 1000-4-2
MAX3488E
MAX3490E
MAX3491E
120Ω
±15kV ESD Protection
The IEC 1000-4-2 standard covers ESD testing and
performance of finished equipment; it does not specifically refer to integrated circuits. The MAX3483E family of
devices helps you design equipment that meets Level 4
(the highest level) of IEC 1000-4-2, without the need for
additional ESD-protection components.
The major difference between tests done using the
Human Body Model and IEC 1000-4-2 is higher peak current in IEC 1000-4-2, because series resistance is lower
in the IEC 1000-4-2 model. Hence, the ESD withstand
voltage measured to IEC 1000-4-2 is generally lower than
that measured using the Human Body Model. Figure 23a
shows the IEC 1000-4-2 model, and Figure 23b shows
the current waveform for the ±8kV IEC 1000-4-2, Level 4
ESD contact-discharge test. test.
Maxim Integrated │ 15
MAX3483E/MAX3485E/
MAX3486E/MAX3488E/
MAX3490E/MAX3491E
RC
1M
CHARGE-CURRENTLIMIT RESI STOR
HIGHVOLTAGE
DC
SOURCE
CS
10 0pF
3.3V-Powered, ±15kV ESD-Protected,
12Mbps and Slew-Rate-Limited
True RS-485/RS-422 Transceivers
RD
37 22²
IP 100%
90%
DISCHARGE
RESISTANCE
STORAGE
CAPACITOR
Ir
PEAK-TO-PEAK RINGING
(NOT DRAWN TO SCALE)
AMPERES
DEVICE
UNDER
TEST
36.8%
10%
0
0
TIME
tRL
tDL
CURRENT WAVEFORM
Figure 22a. Human Body ESD Test Model
Figure 22b. Human Body Current Waveform
I
RC
50 M TO 100 M
CHARGE-CURRENTLIMIT RESI STOR
HIGHVOLTAGE
DC
SOURCE
CS
15 0pF
RD
55 2²
10 0%
90 %
DISCHARGE
RESISTANCE
STORAGE
CAPACITOR
DEVICE
UNDER
TEST
10 %
tR = 0.7ns
TO 1ns
t
30 ns
60 ns
Figure 23a. IEC 1000-4-2 ESD Test Model
Figure 23b. IEC 1000-4-2 ESD Generator Current Waveform
The air-gap test involves approaching the device with a
charged probe. The contact-discharge method connects
the probe to the device before the probe is energized.
Typical Applications
Machine Model
The Machine Model for ESD tests all pins using a 200pF
storage capacitor and zero discharge resistance. Its
objective is to emulate the stress caused when I/O pins
are contacted by handling equipment during test and
assembly. Of course, all pins require this protection, not
just RS-485 inputs and outputs.
www.maximintegrated.com
The MAX3483E/MAX3485E/MAX3486E/MAX3488E/
MAX3490E/MAX3491E transceivers are designed for
bidirectional data communications on multipoint bus
transmission lines. Figures 24 and 25 show typical network applications circuits. These parts can also be used
as line repeaters, with cable lengths longer than 4000
feet, as shown in Figure 21.
To minimize reflections, the line should be terminated
at both ends in its characteristic impedance, and stub
lengths off the main line should be kept as short as
possible. The slew-rate-limited MAX3483E/MAX3488E
and the partially slew-rate-limited MAX3486E are more
tolerant of imperfect termination.
Maxim Integrated │ 16
MAX3483E/MAX3485E/
MAX3486E/MAX3488E/
MAX3490E/MAX3491E
3.3V-Powered, ±15kV ESD-Protected,
12Mbps and Slew-Rate-Limited
True RS-485/RS-422 Transceivers
120Ω
120Ω
B
DI
DE
B
D
D
DE
B
A
A
B
A
A
R
R
RO
RE
DI
RO
RE
R
R
D
D
MAX3483E
MAX3485E
MAX3486E
DE
DI
RO RE
DI
RO RE
DE
Figure 24. MAX3483E/MAX3485E/MAX3486E Typical RS-485 Network
A
R
RO
RE
DE
DI
Y
120Ω
120Ω
D
B
Z
Z
B
D
Y
120Ω
120Ω
Z
Y
B
A
Y
Z
R
A
DE RERO
DE
RE
RO
R
A
R
MAX3488E
MAX3490E
MAX3491E
D
D
DI
B
DI
DI
DE RERO
NOTE: RE AND DE ON MAX3491 ONLY.
Figure 25. MAX3488E/MAX3490E/MAX3491E Full-Duplex RS-485 Network
www.maximintegrated.com
Maxim Integrated │ 17
MAX3483E/MAX3485E/
MAX3486E/MAX3488E/
MAX3490E/MAX3491E
3.3V-Powered, ±15kV ESD-Protected,
12Mbps and Slew-Rate-Limited
True RS-485/RS-422 Transceivers
Ordering Information (continued)
PART
TEMP. RANGE
MAX3485ECSA
0°C to+70°C
8 SO
MAX3485ECPA
0°C to+70°C
8 Plastic DIP
MAX3485EESA
-40°C to+85°C
8 SO
MAX3485EEPA
-40°C to+85°C
8 Plastic DIP
MAX3486ECSA
0°C to +70°C
8 SO
MAX3486ECPA
0°C to +70°C
8 Plastic DIP
MAX3486EESA
-40°C to +85°C
8 SO
MAX3486EEPA
-40°C to +85°C
8 Plastic DIP
MAX3488ECSA
0°C to +70°C
8 SO
MAX3488ECPA
0°C to +70°C
8 Plastic DIP
MAX3488EESA
-40°C to +85°C
8 SO
MAX3488EEPA
-40°C to +85°C
8 Plastic DIP
MAX3490ECSA
0°C to +70°C
8 SO
MAX3490ECPA
0°C to +70°C
8 Plastic DIP
MAX3490EESA
-40°C to +85°C
8 SO
MAX3490EEPA
-40°C to +85°C
8 Plastic DIP
MAX3491ECSD
0°C to +70°C
14 SO
MAX3491ECPD
0°C to +70°C
14 Plastic DIP
MAX3491EESD
-40°C to +85°C
14 SO
MAX3491EEPD
-40°C to +85°C
14 Plastic DIP
www.maximintegrated.com
PIN-PACKAGE
Chip Information
TRANSISTOR COUNT: 761
Maxim Integrated │ 18
MAX3483E/MAX3485E/
MAX3486E/MAX3488E/
MAX3490E/MAX3491E
3.3V-Powered, ±15kV ESD-Protected,
12Mbps and Slew-Rate-Limited
True RS-485/RS-422 Transceivers
Revision History
REVISION
NUMBER
REVISION
DATE
PAGES
CHANGED
0
4/99
Initial release
—
1
5/19
Updated Absolute Maximum Ratings and Package Information section
2
DESCRIPTION
For pricing, delivery, and ordering information, please visit Maxim Integrated’s online storefront at https://www.maximintegrated.com/en/storefront/storefront.html.
Maxim Integrated cannot assume responsibility for use of any circuitry other than circuitry entirely embodied in a Maxim Integrated product. No circuit patent licenses
are implied. Maxim Integrated reserves the right to change the circuitry and specifications without notice at any time. The parametric values (min and max limits)
shown in the Electrical Characteristics table are guaranteed. Other parametric values quoted in this data sheet are provided for guidance.
Maxim Integrated and the Maxim Integrated logo are trademarks of Maxim Integrated Products, Inc.
© 2019 Maxim Integrated Products, Inc. │ 19
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