General Description
The MAX3070E–MAX3079E 3.3V, ±15kV ESD-protected,
RS-485/RS-422 transceivers feature one driver and one
receiver. These devices include fail-safe circuitry, guaranteeing
a logic-high receiver output when receiver inputs are open
or shorted. The receiver outputs a logic-high if all transmitters
on a terminated bus are disabled (high impedance). The
devices include a hot-swap capability to eliminate false
transitions on the bus during power-up or hot insertion.
The MAX3070E/MAX3071E/MAX3072E feature reduced
slew-rate drivers that minimize EMI and reduce reflections
caused by improperly terminated cables, allowing error-
free data transmission up to 250kbps. The MAX3073E/
MAX3074E/MAX3075E also feature slew-rate-limited
drivers but allow transmit speeds up to 500kbps. The
MAX3076E/MAX3077E/MAX3078E driver slew rates are
not limited, making transmit speeds up to 16Mbps possible.
The MAX3079E slew rate is pin-selectable for 250kbps,
500kbps, and 16Mbps.
The MAX3072E/MAX3075E/MAX3078E are intended
for half-duplex communications, and the MAX3070E/
MAX3071E/MAX3073E/MAX3074E/MAX3076E/
MAX3077E are intended for full-duplex communications.
The MAX3079E is selectable for half-duplex or full-duplex
operation. It also features independently programmable
receiver and transmitter output phase through separate
pins.
The MAX3070E–MAX3079E transceivers draw 800μA
of supply current when unloaded, or when fully loaded
with the drivers disabled. All devices have a 1/8-unit load
receiver input impedance, allowing up to 256 transceivers
on the bus.
Applications
●Lighting Systems
●Industrial Control
●Telecom
●Security Systems
●Instrumentation
Benets and Features
●Protection for Robust Performance
• ±15kV Human Body Model ESD on I/O Pins
• True Fail-Safe Receiver While Maintaining
EIA/TIA-485 Compatibility
• Enhanced Slew-Rate-Limiting Facilitates Error-
Free Data Transmission (MAX3070E-MAX3075E/
MAX3079E)
• Hot-Swap Input Structure on DE and RE
●Flexible Feature Set for Ease of Design
• Pin-Selectable Full/Half-Duplex Operation
(MAX3079E)
• Phase Controls to Correct for Twisted-Pair
Reversal (MAX3079E)
• Allows up to 256 Transceivers on the Bus
• Available in Industry-Standard SO and DIP packages
●10µA Shutdown Current Mode for Power Savings
(Except MAX3071E/MAX3074E/MAX3077E)
19-2668; Rev 4; 1/16
Ordering Information at end of data sheet.
Selector Guide, Pin Configurations, and Typical Operating
Circuits appear at end of data sheet.
MAX3070E–MAX3079E +3.3V, ±15kV ESD-Protected, Fail-Safe,
Hot-Swap, RS-485/RS-422 Transceivers
(All voltages referenced to GND)
Supply Voltage (VCC) ............................................................+6V
Control Input Voltage (RE, DE, SLR,
H/F, TXP, RXP) .................................................... -0.3V to +6V
Driver Input Voltage (DI) ..........................................-0.3V to +6V
Driver Output Voltage (Z, Y, A, B) ............................-8V to +13V
Receiver Input Voltage (A, B) ................................... -8V to +13V
Receiver Input Voltage
Full Duplex (A, B) .................................................-8V to +13V
Receiver Output Voltage (RO) ................. -0.3V to (VCC + 0.3V)
Driver Output Current ..................................................... ±250mA
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 10.0mW/°C above +70°C) .. 800mW
Operating Temperature Ranges
MAX307_EE_ _ .............................................. -40°C to +85°C
MAX307_EA_ _ ............................................ -40°C to +125°C
MAX3077EMSA ............................................ -55°C to +125°C
Junction Temperature ...................................................... +150°C
Storage Temperature Range ............................ -65°C to +150°C
Lead Temperature (soldering, 10s) .................................+300°C
(VCC = 3.3V ±10%, TA =TMIN to TMAX, unless otherwise noted. Typical values are at VCC = 3.3V and TA = +25°C.) (Note 1)
PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS
DRIVER
Differential Driver Output VOD
RL = 100Ω (RS422), Figure 1 2 VCC
VRL = 54Ω (RS485), Figure 1 1.5 VCC
No load VCC
Change in Magnitude of
Differential Output Voltage ΔVOD RL = 100Ω or 54Ω, Figure 1 (Note 2) 0.2 V
Driver Common-Mode Output
Voltage VOC RL = 100Ω or 54Ω, Figure 1 VCC/2 3 V
Change in Magnitude of
Common-Mode Voltage ΔVOC RL = 100Ω or 54Ω, Figure 1 (Note 2) 0.2 V
Input High Voltage VIH DE, DI, RE, TXP, RXP, H/F2 V
Input Low Voltage VIL DE, DI, RE, TXP, RXP, H/F0.8 V
Input Hysteresis VHYS DE, DI, RE, TXP, RXP, H/F100 mV
Input Current IIN1 DE, DI, RE ±1 µA
Input Impedance First Transition DE 1 10 kΩ
Input Current IIN2 TXP, RXP, H/F internal pulldown 10 40 µA
SRL Input High Voltage VCC - 0.4 V
SRL Input Middle Voltage VCC x 0.4 VCC x 0.6 V
SRL Input Low Voltage 0.4 V
SRL Input Current SRL = VCC 75 µA
SRL = GND -75
Output Leakage (Y and Z)
Full Duplex IO
DE = GND,
VCC = GND or 3.6V
VIN = +12V 125 µA
VIN = -7V -100
MAX3070E–MAX3079E +3.3V, ±15kV ESD-Protected, Fail-Safe,
Hot-Swap, RS-485/RS-422 Transceivers
www.maximintegrated.com Maxim Integrated
│
2
Absolute Maximum Ratings
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.
DC Electrical Characteristics
(VCC = 3.3V ±10%, TA =TMIN to TMAX, unless otherwise noted. Typical values are at VCC = 3.3V and TA = +25°C.) (Note 1)
Note 1: All currents into the device are positive. All currents out of the device are negative. All voltages are referred to device
ground, unless otherwise noted.
Note 2: ΔVOD and ΔVOC are the changes in VOD and VOC, 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.
PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS
Driver Short-Circuit Output Current IOSD
0 ≤ VOUT ≤ 12V (Note 3) 40 250 mA
-7V ≤ VOUT ≤ VCC (Note 3) -250 -40
Driver Short-Circuit Foldback
Output Current IOSDF
(VCC - 1V) ≤ VOUT ≤ 12V (Note 3) 20 mA
-7V ≤ VOUT ≤ 1V (Note 3) -20
Thermal-Shutdown Threshold TTS 175 °C
Thermal-Shutdown Hysteresis TTSH 15 °C
Input Current (A and B) IA, B
DE = GND,
VCC = GND or 3.6V
VIN = +12V 125 µA
VIN = -7V -100
RECEIVER
Receiver Differential Threshold
Voltage VTH -7V ≤ VCM ≤ 12V -200 -125 -50 mV
Receiver Input Hysteresis ΔVTH VA + VB = 0V 15 mV
RO Output High Voltage VOH IO = -1mA VCC - 0.6 V
RO Output Low Voltage VOL IO = 1mA 0.4 V
Three-State Output Current at
Receiver IOZR 0 ≤ VO ≤ VCC ±1 µA
Receiver Input Resistance RIN -7V ≤ VCM ≤ 12V 96 kΩ
Receiver Output Short-Circuit
Current IOSR 0V ≤ VRO ≤ VCC ±80 mA
SUPPLY CURRENT
Supply Current ICC
No load, RE = 0, DE = VCC 0.8 1.5
mANo load, RE = VCC, DE = VCC 0.8 1.5
No load, RE = 0, DE = 0 0.8 1.5
Supply Current in Shutdown Mode ISHDN RE = VCC, DE = GND 0.05 10 µA
ESD PROTECTION
ESD Protection for Y, Z, A, and B Human Body Model ±15 kV
MAX3070E–MAX3079E +3.3V, ±15kV ESD-Protected, Fail-Safe,
Hot-Swap, RS-485/RS-422 Transceivers
www.maximintegrated.com Maxim Integrated
│
3
DC Electrical Characteristics (continued)
(VCC = 3.3V ±10%, TA = TMIN to TMAX, unless otherwise noted. Typical values are at VCC = 3.3V and TA = +25°C.)
(VCC = 3.3V ±10%, TA = TMIN to TMAX, unless otherwise noted. Typical values are at VCC = 3.3V and TA = +25°C.)
PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS
Driver Propagation Delay tDPLH CL= 50pF, RL= 54Ω, Figures 2 and 3 250 1500 ns
tDPHL 250 1500
Driver Differential Output Rise or
Fall Time tDR , tDF CL= 50pF, RL= 54Ω, Figures 2 and 3 350 1600 ns
Differential Driver Output Skew
|tDPLH - tDPHL|tDSKEW CL= 50pF, RL= 54Ω, Figures 2 and 3 200 ns
Maximum Data Rate 250 kbps
Driver Enable to Output High tDZH Figure 4 2500 ns
Driver Enable to Output Low tDZL Figure 5 2500 ns
Driver Disable Time from Low tDLZ Figure 5 100 ns
Driver Disable Time from High tDHZ Figure 4 100 ns
Driver Enable from Shutdown to
Output High tDZH(SHDN) Figure 4 5500 ns
Driver Enable from Shutdown to
Output Low tDZL(SHDN) Figure 5 5500 ns
Time to Shutdown tSHDN 50 200 600 ns
PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS
Receiver Propagation Delay tRPLH CL = 15pF, Figures 6 and 7 200 ns
tRPHL 200
Receiver Output Skew
|tRPLH - tRPHL|tRSKEW CL = 15pF, Figures 6 and 7 30 ns
Maximum Data Rate 250 kbps
Receiver Enable to Output Low tRZL Figure 8 50 ns
Receiver Enable to Output High tRZH Figure 8 50 ns
Receiver Disable Time from Low tRLZ Figure 8 50 ns
Receiver Disable Time from High tRHZ Figure 8 50 ns
Receiver Enable from Shutdown
to Output High tRZH(SHDN) Figure 8 4000 ns
Receiver Enable from Shutdown
to Output Low tRZL(SHDN) Figure 8 4000 ns
Time to Shutdown tSHDN 50 200 600 ns
MAX3070E–MAX3079E +3.3V, ±15kV ESD-Protected, Fail-Safe,
Hot-Swap, RS-485/RS-422 Transceivers
www.maximintegrated.com Maxim Integrated
│
4
Driver Switching Characteristics
MAX3070E/MAX3071E/MAX3072E/MAX3079E with SRL = UNCONNECTED (250kbps)
Receiver Switching Characteristics
MAX3070E/MAX3071E/MAX3072E/MAX3079E with SRL = UNCONNECTED (250kbps)
Switching Characteristics
(VCC = 3.3V ±10%, TA = TMIN to TMAX, unless otherwise noted. Typical values are at VCC = 3.3V and TA = +25°C.)
(VCC = 3.3V ±10%, TA = TMIN to TMAX, unless otherwise noted. Typical values are at VCC = 3.3V and TA = +25°C.)
PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS
Driver Propagation Delay tDPLH CL = 50pF, RL = 54Ω, Figures 2 and 3 180 800 ns
tDPHL 180 800
Driver Differential Output Rise or
Fall Time tDR , tDF CL = 50pF, RL = 54Ω, Figures 2 and 3 200 800 ns
Differential Driver Output Skew
|tDPLH - tDPHL|tDSKEW CL = 50pF, RL = 54Ω, Figures 2 and 3 100 ns
Maximum Data Rate 500 kbps
Driver Enable to Output High tDZH Figure 4 2500 ns
Driver Enable to Output Low tDZL Figure 5 2500 ns
Driver Disable Time from Low tDLZ Figure 5 100 ns
Driver Disable Time from High tDHZ Figure 4 100 ns
Driver Enable from Shutdown to
Output High tDZH(SHDN) Figure 4 4500 ns
Driver Enable from Shutdown to
Output Low tDZL(SHDN) Figure 5 4500 ns
Time to Shutdown tSHDN 50 200 600 ns
PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS
Receiver Propagation Delay tRPLH CL = 15pF, Figures 6 and 7 200 ns
tRPHL 200
Receiver Output Skew
|tRPLH - tRPHL|tRSKEW CL = 15pF, Figures 6 and 7 30 ns
Maximum Data Rate 500 kbps
Receiver Enable to Output Low tRZL Figure 8 50 ns
Receiver Enable to Output High tRZH Figure 8 50 ns
Receiver Disable Time from Low tRLZ Figure 8 50 ns
Receiver Disable Time from High tRHZ Figure 8 50 ns
Receiver Enable from Shutdown
to Output High tRZH(SHDN) Figure 8 4000 ns
Receiver Enable from Shutdown
to Output Low tRZL(SHDN) Figure 8 4000 ns
Time to Shutdown tSHDN 50 200 600 ns
MAX3070E–MAX3079E +3.3V, ±15kV ESD-Protected, Fail-Safe,
Hot-Swap, RS-485/RS-422 Transceivers
www.maximintegrated.com Maxim Integrated
│
5
Driver Switching Characteristics
MAX3073E/MAX3074E/MAX3075E/MAX3079E with SRL = VCC (500kbps)
Receiver Switching Characteristics
MAX3073E/MAX3074E/MAX3075E/MAX3079E with SRL = VCC (500kbps)
(VCC = 3.3V ±10%, TA = TMIN to TMAX, unless otherwise noted. Typical values are at VCC = 3.3V and TA = +25°C.)
(VCC = 3.3V ±10%, TA = TMIN to TMAX, unless otherwise noted. Typical values are at VCC = 3.3V and TA = +25°C.)
PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS
Driver Propagation Delay tDPLH CL = 50pF, RL= 54Ω, Figures 2 and 3 50 ns
tDPHL 50
Driver Differential Output Rise or
Fall Time tDR , tDF CL = 50pF, RL= 54Ω, Figures 2 and 3 15 ns
Differential Driver Output Skew
|tDPLH - tDPHL|tDSKEW CL = 50pF, RL= 54Ω, Figures 2 and 3 8 ns
Maximum Data Rate 16 Mbps
Driver Enable to Output High tDZH Figure 4 150 ns
Driver Enable to Output Low tDZL Figure 5 150 ns
Driver Disable Time from Low tDLZ Figure 5 100 ns
Driver Disable Time from High tDHZ Figure 4 100 ns
Driver Enable from Shutdown to
Output High tDZH(SHDN) Figure 4 1250 1800 ns
Driver Enable from Shutdown to
Output Low tDZL(SHDN) Figure 5 1250 1800 ns
Time to Shutdown tSHDN 50 200 600 ns
PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS
Receiver Propagation Delay tRPLH CL = 15pF, Figures 6 and 7 40 75 ns
tRPHL 40 75
Receiver Output Skew
|tRPLH - tRPHL|tRSKEW CL = 15pF, Figures 6 and 7 8 ns
Maximum Data Rate 16 Mbps
Receiver Enable to Output Low tRZL Figure 8 50 ns
Receiver Enable to Output High tRZH Figure 8 50 ns
Receiver Disable Time from Low tRLZ Figure 8 50 ns
Receiver Disable Time from High tRHZ Figure 8 50 ns
Receiver Enable from Shutdown
to Output High tRZH(SHDN) Figure 8 1800 ns
Receiver Enable from Shutdown
to Output Low tRZL(SHDN) Figure 8 1800 ns
Time to Shutdown tSHDN 50 200 600 ns
MAX3070E–MAX3079E +3.3V, ±15kV ESD-Protected, Fail-Safe,
Hot-Swap, RS-485/RS-422 Transceivers
www.maximintegrated.com Maxim Integrated
│
6
Driver Switching Characteristics
MAX3076E/MAX3077E/MAX3078E/MAX3079E with SRL = GND (16Mbps)
Receiver Switching Characteristics
MAX3076E/MAX3077E/MAX3078E/MAX3079E with SRL = GND (16Mbps)
(VCC = 3.3V, TA = +25°C, unless otherwise noted. Note: The MAX3077EMSA/PR meets specication over temperature.)
OUTPUT CURRENT
vs. RECEIVER OUTPUT HIGH VOLTAGE
MAX3070E toc02
OUTPUT HIGH VOLTAGE (V)
OUTPUT CURRENT (mA)
3.02.52.01.51.00.5
5
10
15
20
25
30
0
0 3.5
OUTPUT CURRENT
vs. RECEIVER OUTPUT LOW VOLTAGE
MAX3070E toc03
OUTPUT HIGH VOLTAGE (V)
OUTPUT CURRENT (mA)
3.02.52.01.51.00.5
5
10
15
20
25
30
35
0
0 3.5
RECEIVER OUTPUT HIGH VOLTAGE
vs. TEMPERATURE
MAX3070E toc04
TEMPERATURE (°C)
OUTPUT HIGH VOLTAGE (V)
1007550250-25
3.05
3.10
3.15
3.20
3.25
3.30
3.00
-50 125
IO = -1mA
RECEIVER OUTPUT LOW VOLTAGE
vs. TEMPERATURE
MAX3070E toc05
TEMPERATURE (°C)
OUTPUT LOW VOLTAGE (V)
10075-25 0 25 50
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
0
-50 125
IO = -1mA
DRIVER OUTPUT CURRENT
vs. DIFFERENTIAL OUTPUT VOLTAGE
MAX3070E toc06
DIFFERENTIAL OUTPUT VOLTAGE (V)
OUTPUT CURRENT (mA)
3.02.51.5 2.01.00.5
10
20
30
40
50
60
70
80
90
100
0
0 3.5
DRIVER DIFFERENTIAL OUTPUT VOLTAGE
vs. TEMPERATURE
XMAX3070E toc07
TEMPERATURE (°C)
DIFFERENTIAL OUTPUT VOLTAGE (V)
1007525 500-25
1.70
1.80
1.90
2.00
2.10
2.20
2.30
2.40
2.50
2.60
1.60
-50 125
RL = 54Ω
SUPPLY CURRENT vs. TEMPERATURE
MAX3070E toc01
TEMPERATURE (°C)
SUPPLY CURRENT (mA)
1007550250-25
0.6
0.7
0.8
0.9
1.0
0.5
-50 125
DE = VCC
DE = 0
OUTPUT CURRENT
vs. TRANSMITTER OUTPUT HIGH VOLTAGE
MAX3070E toc08
OUTPUT HIGH VOLTAGE (V)
OUTPUT CURRENT (mA)
32-6 -5 -4 -2 -1 0-3 1
20
40
60
80
100
120
140
160
0
-7 4
OUTPUT CURRENT
vs. TRANSMITTER OUTPUT LOW VOLTAGE
MAX3070E toc09
OUTPUT LOW VOLTAGE (V)
OUTPUT CURRENT (mA)
108642
20
40
60
80
100
120
140
160
180
0
0 12
MAX3070E–MAX3079E +3.3V, ±15kV ESD-Protected, Fail-Safe,
Hot-Swap, RS-485/RS-422 Transceivers
Maxim Integrated
│
7
www.maximintegrated.com
Typical Operating Characteristics
(VCC = 3.3V, TA = +25°C, unless otherwise noted. Note: The MAX3077EMSA/PR meets specication over temperature.)
SHUTDOWN CURRENT
vs. TEMPERATURE
MAX3070E toc10
TEMPERATURE (°C)
SHUTDOWN CURRENT (mA)
1007525 500-25
0.2
0.4
0.6
0.8
1.0
1.2
1.4
1.6
1.8
2.0
0
-50 125
DRIVER PROPAGATION DELAY
vs. TEMPERATURE (250kbps)
MAX3070E toc11
TEMPERATURE (°C)
DRIVER PROPAGATION DELAY (ns)
1007550250-25
600
700
800
900
1000
500
-50 125
tDPLH
tDPHL
DRIVER PROPAGATION DELAY
vs. TEMPERATURE (500kbps)
MAX3070E toc12
TEMPERATURE (°C)
DRIVER PROPAGATION DELAY (ns)
1007550250-25
250
300
350
400
450
500
200
-50 125
tDPLH
tDPHL
DRIVER PROPAGATION DELAY
vs. TEMPERATURE (16Mbps)
MAX3070E toc13
TEMPERATURE (°C)
DRIVER PROPAGATION DELAY (ns)
1007550250-25
5
10
15
20
25
30
0
-50 125
tDPLH
tDPHL
RECEIVER PROPAGATION DELAY
vs. TEMPERATURE (250kbps AND 500kbps)
MAX3070E toc14
TEMPERATURE (°C)
DRIVER PROPAGATION DELAY (ns)
1007550250-25
30
60
90
120
150
0
-50 125
tDPLH
tDPHL
RECEIVER PROPAGATION DELAY
vs. TEMPERATURE (16Mbps)
MAX3070E toc15
TEMPERATURE (°C)
RECEIVER PROPAGATION DELAY (ns)
1007550250-25
10
20
30
40
50
60
70
0
-50 125
tDPLH
tDPHL
DRIVER PROPAGATION DELAY (250kbps)
MAX3070E toc16
1µs/div
VY - VZ
2V/div
DI
2V/div
RECEIVER PROPAGATION DELAY
(250kbps AND 500kbps)
MAX3070E toc17
200ns/div
VA - VB
1V/div
RO
2V/div
MAX3070E–MAX3079E +3.3V, ±15kV ESD-Protected, Fail-Safe,
Hot-Swap, RS-485/RS-422 Transceivers
Maxim Integrated
│
8
www.maximintegrated.com
Typical Operating Characteristics (continued)
(VCC = 3.3V, TA = +25°C, unless otherwise noted. Note: The MAX3077EMSA/PR meets specication over temperature.)
Figure 1. Driver DC Test Load Figure 2. Driver Timing Test Circuit
Figure 3. Driver Propagation Delays
DRIVER PROPAGATION DELAY (500kbps)
MAX3070E toc18
400ns/div
VY - VZ
2V/div
DI
2V/div
DRIVER PROPAGATION DELAY (16Mbps)
MAX3070E toc19
10ns/div
VZ
1V/div
VY
1V/div
DI
2V/div
RECEIVER PROPAGATION DELAY (16Mbps)
MAX3070E toc20
20ns/div
VA
1V/div
VB
1V/div
RO
2V/div
Y
Z
VOD
VOC
RL/2
RL/2
DI
VCC
0
Z
Y
VO
0
-VO
VO
VCC/2
tDPLH tDPHL
1/2 VO
10%
tDR
90% 90%
1/2 VO
10%
tDF
VDIFF = V (Y) - V (Z)
VDIFF
tSKEW = | tDPLH - tDPHL |
DI
DE
3V
Z
Y
VOD RLCL
MAX3070E–MAX3079E +3.3V, ±15kV ESD-Protected, Fail-Safe,
Hot-Swap, RS-485/RS-422 Transceivers
Maxim Integrated
│
9
www.maximintegrated.com
Typical Operating Characteristics (continued)
Test Circuits and Waveforms
Figure 4. Driver Enable and Disable Times (tDHZ, tDZH, tDZH(SHDN))
Figure 5. Driver Enable and Disable Times (tDHZ, tDZH, tDZH(SHDN))
DE
OUT
tDHZ
0
VCC
VCC / 2
0.25V
0
VOH
GENERATOR
0 OR 3V
S1
50Ω
DOUT
tDZH, tDZH(SHDN)
VOM = (0 + VOH) / 2
RL = 500Ω
CL
50pF
DE
VCC
OUT
tDLZ
0
VCC
VCC / 2
GENERATOR
0 OR 3V
S1
50Ω
DOUT
tDZL, tDZL(SHDN)
VOM = (VOL + VCC) / 2
RL = 500Ω
CL
50pF
VOL 0.25V
VCC
MAX3070E–MAX3079E +3.3V, ±15kV ESD-Protected, Fail-Safe,
Hot-Swap, RS-485/RS-422 Transceivers
www.maximintegrated.com Maxim Integrated
│
10
Test Circuits and Waveforms (continued)
Figure 8. Receiver Enable and Disable Times
Figure 6. Receiver Propagation Delay Test Circuit Figure 7. Receiver Propagation Delays
S1 OPEN
S2 CLOSED
S3 = +1.5V
RO
3V
0
0
VOH
VOH / 2
S1 OPEN
S2 CLOSED
S3 = +1.5V
tRHZ
3V
0
0
VOH
0.25V
1.5V
S1 CLOSED
S2 OPEN
S3 = -1.5V
3V
0
VOL
VCC
1.5V
S1 CLOSED
S2 OPEN
S3 = -1.5V
tRLZ
3V
0
VOL
VCC
1.5V
0.25V
GENERATOR
VCC
+1.5V
1kΩ
CL
15pF S2
S1
50Ω
S3
-1.5V R
VID
RE
RO
RE
RO
RE
RO
RE
tRZH, tRZH(SHDN) tRZL, tRZL(SHDN)
(VOL + VCC) / 2
VID R
B
A
RECEIVER
OUTPUT
ATE
A
B
RO
VOH
1.5V
tRPLH
tRPHL
VOL
+1V
-1V
THE RISE TIME AND FALL TIME OF INPUTS A AND B < 4ns
MAX3070E–MAX3079E +3.3V, ±15kV ESD-Protected, Fail-Safe,
Hot-Swap, RS-485/RS-422 Transceivers
www.maximintegrated.com Maxim Integrated
│
11
Test Circuits and Waveforms (continued)
PIN
NAME FUNCTION
MAX3070E
MAX3073E
MAX3076E
MAX3071E
MAX3074E
MAX3077E
MAX3072E
MAX3075E
MAX3078E
MAX3079E
FULL-DUPLEX
DEVICES
HALF-
DUPLEX
DEVICES
FULL-
DUPLEX
MODE
HALF-
DUPLEX
MODE
— — — 1 1 H/F
Half-/Full-Duplex Select Pin. Connect H/F to VCC for half-
duplex mode; connect to GND or leave unconnected for
full-duplex mode.
2 2 1 2 2 RO Receiver Output. When RE is low and if (A - B) ≥ -50mV,
RO is high; if (A - B) ≤ -200mV, RO is low.
3 — 2 3 3 RE
Receiver Output Enable. Drive RE low to enable RO; RO
is high impedance when RE is high. Drive RE high and DE
low to enter low-power shutdown mode. RE is a hot-swap
input (see the Hot-Swap Capability section for details).
4 — 3 4 4 DE
Driver Output Enable. Drive DE high to enable driver
outputs. These outputs are high impedance when DE
is low. Drive RE high and DE low to enter low-power
shutdown mode. DE is a hot-swap input (see the Hot-
Swap Capability section for details).
5 3 4 5 5 DI
Driver Input. With DE high, a low on DI forces noninverting
output low and inverting output high. Similarly, a high on DI
forces noninverting output high and inverting output low.
— — — 6 6 SRL
Slew-Rate Limit Selector Pin. Connect SRL to ground for
16Mbps communication rate; connect to VCC for 500kbps
communication rate. Leave unconnected for 250kbps
communication rate.
6, 7 4 5 7 7 GND Ground
— — — 8 8 TXP
Transmitter Phase. Connect TXP to ground or leave
unconnected for normal transmitter phase/polarity.
Connect to VCC to invert the transmitter phase/polarity.
9 5 — 9 — Y Noninverting Driver Output
— — — — 9 Y Noninverting Driver Output and Noninverting Receiver
Input*
10 6 — 10 — Z Inverting Driver Output
— — — — 10 Z Inverting Driver Output and Inverting Receiver Input*
11 7 — 11 — B Inverting Receiver Input
— — — — 11 B Receiver Input Resistors*
— — 7 — — B Inverting Receiver Input and Inverting Driver Output
MAX3070E–MAX3079E +3.3V, ±15kV ESD-Protected, Fail-Safe,
Hot-Swap, RS-485/RS-422 Transceivers
www.maximintegrated.com Maxim Integrated
│
12
Pin Description
*MAX3079E only. In half-duplex mode, the driver outputs serve as receiver inputs. The full-duplex receiver inputs (A and B) still have
a 1/8-unit load, but are not connected to the receiver.
TRANSMITTING
INPUTS OUTPUTS
RE DE DI Z Y
X 1 1 0 1
X 1 0 1 0
0 0 X High-Z High-Z
1 0 X Shutdown
RECEIVING
INPUTS OUTPUT
RE DE A, B RO
0 X ≥ -50mV 1
0 X ≤ -200mV 0
0 X Open/
shorted 1
1 1 X High-Z
1 0 X Shutdown
TRANSMITTING
INPUT OUTPUTS
DI Z Y
1 0 1
0 1 0
RECEIVING
INPUTS OUTPUT
A, B RO
≥ -50mV 1
≤ -200mV 0
Open/shorted 1
PIN
NAME FUNCTION
MAX3070E
MAX3073E
MAX3076E
MAX3071E
MAX3074E
MAX3077E
MAX3072E
MAX3075E
MAX3078E
MAX3079E
FULL-DUPLEX
DEVICES
HALF-
DUPLEX
DEVICES
FULL-
DUPLEX
MODE
HALF-
DUPLEX
MODE
12 8 — 12 — A Noninverting Receiver Input
— — — — 12 A Receiver Input Resistors*
— — 6 — — A Noninverting Receiver Input and Noninverting Driver
Output
— — — 13 13 RXP
Receiver Phase. Connect RXP to GND or leave
unconnected for normal transmitter phase/polarity.
Connect to VCC to invert receiver phase/polarity.
14 1 8 14 14 VCC
Positive Supply VCC = 3.3V ±10%. Bypass VCC to GND
with a 0.1µF capacitor.
1, 8, 13 — — — — N.C. No Connect. Not internally connected. Can be connected
to GND.
MAX3070E–MAX3079E +3.3V, ±15kV ESD-Protected, Fail-Safe,
Hot-Swap, RS-485/RS-422 Transceivers
www.maximintegrated.com Maxim Integrated
│
13
Pin Description (continued)
Function Tables
MAX3070E/MAX3073E/MAX3076E MAX3071E/MAX3074E/MAX3077E
X = Don’t care; shutdown mode, driver and receiver outputs are high impedance.
TRANSMITTING
INPUTS OUTPUTS
RE DE DI B/Z A/Y
X 1 1 0 1
X 1 0 1 0
0 0 X High-Z High-Z
1 0 X Shutdown
RECEIVING
INPUTS OUTPUTS
RE DE A-B RO
0 X ≥ -50mV 1
0 X ≤ -200mV 0
0 X Open/
shorted 1
1 1 X High-Z
1 0 X Shutdown
TRANSMITTING
INPUTS OUTPUTS
TXP RE DE DI Z Y
0 X 1 1 0 1
0 X 1 0 1 0
1 X 1 1 1 0
1 X 1 0 0 1
X 0 0 X High-Z High-Z
X 1 0 X Shutdown
RECEIVING
INPUTS OUTPUTS
H/FRXP RE DE A, B Y, Z RO
0 0 0 X > -50mV X 1
0 0 0 X < -200mV X 0
0 1 0 X > -50mV X 0
0 1 0 X < -200mV X 1
1 0 0 0 X > -50mV 1
1 0 0 0 X < -200mV 0
1 1 0 0 X > -50mV 0
1 1 0 0 X < -200mV 1
0 0 0 X Open/shorted X 1
1 0 0 0 X Open/shorted 1
0 1 0 X Open/shorted X 0
1 1 0 0 X Open/shorted 0
X X 1 1 X X High-Z
X X 1 0 X X Shutdown
MAX3070E–MAX3079E +3.3V, ±15kV ESD-Protected, Fail-Safe,
Hot-Swap, RS-485/RS-422 Transceivers
www.maximintegrated.com Maxim Integrated
│
14
Function Tables (continued)
MAX3072E/MAX3075E/MAX3078E
MAX3079E
Detailed Description
The MAX3070E–MAX3079E high-speed transceivers for
RS-485/RS-422 communication contain one driver and
one receiver. These devices feature fail-safe circuitry,
which guarantees a logic-high receiver output when
the receiver inputs are open or shorted, or when they
are connected to a terminated transmission line with
all drivers disabled (see the Fail-Safe section). The
devices also feature a hot-swap capability allowing line
insertion without erroneous data transfer (see the Hot-
Swap Capability section). The MAX3070E/MAX3071E/
MAX3072E feature reduced slew-rate drivers that
minimize EMI and reduce reflections caused by improperly
terminated cables, allowing error-free data transmission
up to 250kbps. The MAX3073E/MAX3074E/MAX3075E
also offer slew-rate limits allowing transmit speeds up
to 500kbps. The MAX3076E/MAX3077E/MAX3078Es’
driver slew rates are not limited, making transmit speeds
up to 16Mbps possible. The MAX3079E’s slew rate is
selectable between 250kbps, 500kbps, and 16Mbps by
driving a selector pin with a three-state driver.
The MAX3072E/MAX3075E/MAX3078E are half-duplex
transceivers, while the MAX3070E/MAX3071E/MAX3073E/
MAX3074E/MAX3076E/MAX3077E are full-duplex transceivers.
The MAX3079E is selectable between half and full-duplex
communication by driving a selector pin (SRL) high or low,
respectively.
All devices operate from a single 3.3V supply. Drivers are
output short-circuit current limited. Thermal-shutdown circuitry
protects drivers against excessive power dissipation. When
activated, the thermal-shutdown circuitry places the driver
outputs into a high-impedance state.
Receiver Input Filtering
The receivers of the MAX3070E–MAX3075E, and the
MAX3079E when operating in 250kbps or 500kbps mode,
incorporate input filtering in addition to input hysteresis.
This filtering enhances noise immunity with differential
signals that have very slow rise and fall times. Receiver
propagation delay increases by 25% due to this filtering.
Fail-Safe
The MAX3070E family guarantees a logic-high receiver
output when the receiver inputs are shorted or open, or
when they are connected to a terminated transmission
line with all drivers disabled. This is done by setting the
receiver input threshold between -50mV and -200mV. If
the differential receiver input voltage (A - B) is greater
than or equal to -50mV, RO is logic-high. If A - B is less
than or equal to -200mV, RO is logic-low. In the case of a
terminated bus with all transmitters disabled, the receiver’s
differential input voltage is pulled to 0V by the termination.
With the receiver thresholds of the MAX3070E family, this
results in a logic high with a 50mV minimum noise margin.
Unlike previous fail-safe devices, the -50mV to -200mV
threshold complies with the ±200mV EIA/TIA-485 standard.
Hot-Swap Capability
(Except MAX3071E/MAX3074E/MAX3077E)
Hot-Swap Inputs
When circuit boards are inserted into a hot, or powered,
backplane, differential disturbances to the data bus can
lead to data errors. Upon initial circuit board insertion,
the data communication processor undergoes its own
power-up sequence. During this period, the processor’s
logic-output drivers are high impedance and are unable to
drive the DE and RE inputs of these devices to a defined
logic level. Leakage currents up to ±10μA from the high-
impedance state of the processor’s logic drivers could
cause standard CMOS enable inputs of a transceiver to
drift to an incorrect logic level. Additionally, parasitic circuit
board capacitance could cause coupling of VCC or GND
to the enable inputs. Without the hot-swap capability,
these factors could improperly enable the transceiver’s
driver or receiver.
When VCC rises, an internal pulldown circuit holds DE
low and RE high. After the initial power-up sequence, the
pulldown circuit becomes transparent, resetting the hot-
swap tolerable input.
Hot-Swap Input Circuitry
The enable inputs feature hot-swap capability. At the input
there are two NMOS devices, M1 and M2 (Figure 9).
When VCC ramps from zero, an internal 10μs timer turns
on M2 and sets the SR latch, which also turns on M1.
Transistors M2, a 500μA current sink, and M1, a 100μA
current sink, pull DE to GND through a 5kΩ resistor. M2 is
designed to pull DE to the disabled state against an external
parasitic capacitance up to 100pF that can drive DE high.
After 10μs, the timer deactivates M2 while M1 remains on,
holding DE low against three-state leakages that can drive
DE high. M1 remains on until an external source overcomes
the required input current. At this time, the SR latch resets
and M1 turns off. When M1 turns off, DE reverts to a standard,
high-impedance CMOS input. Whenever VCC drops
below 1V, the hot-swap input is reset.
For RE there is a complementary circuit employing two
PMOS devices pulling RE to VCC.
MAX3070E–MAX3079E +3.3V, ±15kV ESD-Protected, Fail-Safe,
Hot-Swap, RS-485/RS-422 Transceivers
www.maximintegrated.com Maxim Integrated
│
15
MAX3079E Programming
The MAX3079E has several programmable operating
modes. Transmitter rise and fall times are programmable,
resulting in maximum data rates of 250kbps, 500kbps,
and 16Mbps. To select the desired data rate, drive SRL to
one of three possible states by using a three-state driver:
VCC, GND, or unconnected. For 250kbps operation, set
the three-state device in high-impedance mode or leave
SRL unconnected. For 500kbps operation, drive SRL high
or connect it to VCC. For 16Mbps operation, drive SRL
low or connect it to GND. SRL can be changed during
operation without interrupting data communications.
Occasionally, twisted-pair lines are connected backward
from normal orientation. The MAX3079E has two pins that
invert the phase of the driver and the receiver to correct
this problem. For normal operation, drive TXP and RXP
low, connect them to ground, or leave them unconnected
(internal pulldown). To invert the driver phase, drive TXP
high or connect it to VCC. To invert the receiver phase,
drive RXP high or connect it to VCC. Note that the receiver
threshold is positive when RXP is high.
The MAX3079E can operate in full/half-duplex mode.
Drive the H/F pin low, leave it unconnected (internal
pulldown), or connect it to GND for full-duplex operation.
Drive H/F high for half-duplex operation. In full-duplex
mode, the pin configuration of the driver and receiver is
the same as that of a MAX3070E. In half-duplex mode,
the receiver inputs are switched to the driver outputs, con-
necting outputs Y and Z to inputs A and B, respectively.
In half-duplex mode, the internal full-duplex receiver input
resistors are still connected to pins 11 and 12.
±15kV ESD Protection
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 MAX3070E
family of devices have extra protection against static
electricity. Maxim’s engineers have developed state-of-
the-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, the devices keep
working without latchup or damage.
ESD protection can be tested in various ways. The transmitter
outputs and receiver inputs of the devices are characterized
for protection to the following limits:
●±15kV using the Human Body Model
●±6kV using the Contact Discharge method specified
in IEC 1000-4-2
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 10a shows the Human Body Model, and Figure 10b
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
The IEC 1000-4-2 standard covers ESD testing and
performance of finished equipment. However, it does not
specifically refer to integrated circuits. The MAX3070E
family of devices helps you design equipment to meet 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
Figure 9. Simplified Structure of the Driver Enable Pin (DE)
DE DE
(HOT SWAP)
5kΩ
TIMER
TIMER
VCC
10ms
M2M1
500mA
100mA
SR LATCH
MAX3070E–MAX3079E +3.3V, ±15kV ESD-Protected, Fail-Safe,
Hot-Swap, RS-485/RS-422 Transceivers
www.maximintegrated.com Maxim Integrated
│
16
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 10c
shows the IEC 1000-4-2 model, and Figure 10d shows
the current waveform for IEC 1000-4-2 ESD Contact
Discharge test.
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.
Machine Model
The machine model for ESD tests all pins using a 200pF
storage capacitor and zero discharge resistance. The
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.
Applications Information
256 Transceivers on the Bus
The standard RS-485 receiver input impedance is 12kΩ
(1-unit load), and the standard driver can drive up to
32-unit loads. The MAX3070E family of transceivers has
a 1/8-unit load receiver input impedance (96kΩ), allowing
up to 256 transceivers to be connected in parallel on one
communication line. Any combination of these devices as
well as other RS-485 transceivers with a total of 32-unit
loads or fewer can be connected to the line.
Reduced EMI and Reections
The MAX3070E/MAX3071E/MAX3072E feature reduced
slew-rate drivers that minimize EMI and reduce reflections
caused by improperly terminated cables, allowing error-
free data transmission up to 250kbps. The MAX3073E/
MAX3074E/MAX3075E offer higher driver output slew-
rate limits, allowing transmit speeds up to 500kbps.
The MAX3079E with SRL = VCC or unconnected, are
slew-rate limited. With SRL unconnected, the MAX3079E
error-free data transmission is up to 250kbps; with SRL
connected to VCC the data transmit speeds up to 500kbps.
Figure 10a. Human Body ESD Test Model
Figure 10c. IEC 1000-4-2 ESD Test Model
Figure 10b. Human Body Current Waveform
Figure 10d. IEC 1000-4-2 ESD Generator Current Waveform
CHARGE-CURRENT-
LIMIT RESISTOR
DISCHARGE
RESISTANCE
STORAGE
CAPACITOR
Cs
100pF
RC
1MΩ
RD
1500Ω
HIGH-
VOLTAGE
DC
SOURCE
DEVICE
UNDER
TEST
CHARGE-CURRENT-
LIMIT RESISTOR
DISCHARGE
RESISTANCE
STORAGE
CAPACITOR
Cs
150pF
RC
50MΩ TO 100MΩ
RD
330Ω
HIGH-
VOLTAGE
DC
SOURCE
DEVICE
UNDER
TEST
IP 100%
90%
36.8%
tRL TIME
tDL
CURRENT WAVEFORM
PEAK-TO-PEAK RINGING
(NOT DRAWN TO SCALE)
Ir
10%
0
0
AMPS
tr = 0.7ns TO 1ns 30ns
60ns
t
100%
90%
10%
IPEAK
I
MAX3070E–MAX3079E +3.3V, ±15kV ESD-Protected, Fail-Safe,
Hot-Swap, RS-485/RS-422 Transceivers
www.maximintegrated.com Maxim Integrated
│
17
Low-Power Shutdown Mode
(Except MAX3071E/MAX3074E/MAX3077E)
Low-power shutdown mode is initiated by bringing both
RE high and DE low. In shutdown, the devices typically
draw only 50nA of supply current.
RE and DE can be driven simultaneously; the parts are
guaranteed not to enter shutdown if RE is high and DE is
low for less than 50ns. If the inputs are in this state for at
least 600ns, the parts are guaranteed to enter shutdown.
Enable times tZH and tZL (see the Switching Characteristics
section) assume the part was not in a low-power shutdown
state. Enable times tZH(SHDN) and tZL(SHDN) assume the
parts were shut down. It takes drivers and receivers longer
to become enabled from low-power shutdown mode
(tZH(SHDN), tZL(SHDN)) than from driver/receiver-disable
mode (tZH, tZL).
Driver Output Protection
Two mechanisms prevent excessive output current and
power dissipation caused by faults or by bus contention.
The first, a foldback current limit on the output stage,
provides immediate protection against short circuits over
the whole common-mode voltage range (see the Typical
Operating Characteristics). The second, a thermal-shutdown
circuit, forces the driver outputs into a high-impedance
state if the die temperature becomes excessive.
Line Length
The RS-485/RS-422 standard covers line lengths up
to 4000ft. For line lengths greater than 4000ft, use the
repeater application shown in Figure 11.
Typical Applications
The MAX3072E/MAX3075E/MAX3078E/MAX3079E
transceivers are designed for bidirectional data
communications on multipoint bus transmission lines.
Figure 12 and Figure 13 show typical network application
circuits.
To minimize reflections, terminate the line at both ends
in its characteristic impedance, and keep stub lengths
off the main line as short as possible. The slew-rate-
limited MAX3072E/MAX3075E and the two modes of the
MAX3079E are more tolerant of imperfect termination.
Figure 11. Line Repeater for MAX3070E/MAX3071E/
MAX3073E/ MAX3074E/MAX3076E/MAX3077E/MAX3079E in
Full-Duplex Mode
Figure 12. Typical Half-Duplex RS-485 Network
RO
DI
DE
R
D
MAX3070E/MAX3071E/MAX3073E/
MAX3074E/MAX3076E/MAX3077E/
MAX3079E (FULL-DUPLEX)
RE 120Ω
120Ω
A
B
Z
Y
DATA IN
DATA OUT
DI RO DE
A
B
RE
RO
RO
RO
DI
DI
DI
DE
DE
DE
DD
D
R
R
R
B B
B
AAA
120Ω120Ω
D
R
MAX3072E
MAX3075E
MAX3078E
MAX3079E (HALF-DUPLEX) RERE
RE
MAX3070E–MAX3079E +3.3V, ±15kV ESD-Protected, Fail-Safe,
Hot-Swap, RS-485/RS-422 Transceivers
www.maximintegrated.com Maxim Integrated
│
18
Chip Information
PROCESS: BiCMOS
Figure 13. Typical Full-Duplex RS-485 Network
PART HALF/FULL-
DUPLEX
DATA RATE
(MBPS)
SLEW-RATE
LIMITED
LOW-POWER
SHUTDOWN
RECEIVER/
DRIVER
ENABLE
TRANSCEIVERS
ON BUS PINS
MAX3070E Full 0.250 Yes Yes Yes 256 14
MAX3071E Full 0.250 Yes No No 256 8
MAX3072E Half 0.250 Yes Yes Yes 256 8
MAX3073E Full 0.5 Yes Yes Yes 256 14
MAX3074E Full 0.5 Yes No No 256 8
MAX3075E Half 0.5 Yes Yes Yes 256 8
MAX3076E Full 16 No Yes Yes 256 14
MAX3077E Full 16 No No No 256 8
MAX3078E Half 16 No Yes Yes 256 8
MAX3079E Selectable Selectable Selectable Yes Yes 256 14
RO
DI
DE
R120Ω
120Ω
D
MAX3070E
MAX3073E
MAX3076E
MAX3079E (FULL-DUPLEX)
RE
RO
DI
DE
R
D
RE
120Ω
120Ω
A
B
Z
Y
A
B
Z
Y
RO
DI DE
R
D
RE
Y Z B A
RO
DI DE
R
D
RE
Y Z B A
MAX3070E–MAX3079E +3.3V, ±15kV ESD-Protected, Fail-Safe,
Hot-Swap, RS-485/RS-422 Transceivers
www.maximintegrated.com Maxim Integrated
│
19
Selector Guide
MAX3070E
MAX3073E
MAX3076E
Rt
Rt
DE VCC
RE
GND
VCC RE
GND DE
RO
DI
9
10
12
11
B
A
Z
Y
0.1µF
5
RO
N.C.
DI
2
1, 8, 13
36, 7
14
4
VCC
N.C.
N.C.
A
B
Z
Y
N.C.
RO
RE
DE
DI
GND
GND
D
D
RD
R
TYPICAL FULL-DUPLEX OPERATING CIRCUIT
14
13
12
11
10
9
8
1
2
3
4
5
6
7
DIP/SO
R
MAX3071E
MAX3074E
MAX3077E
Rt
Rt
VCC
GND
VCC
GND
RO
DI
5
6
8
7
B
A
Z
Y
0.1µF
3
RO
DI
2
4
1
R
D
D
RD
R
TYPICAL FULL-DUPLEX OPERATING CIRCUIT
VCC
RO
DI
GND
A
B
Z
Y
8
7
6
5
1
2
3
4
DIP/SO
MAX3072E
MAX3075E
MAX3078E
Rt
Rt
DE
RE
B
A
B
A
0.1µF
TYPICAL HALF-DUPLEX OPERATING CIRCUIT
NOTE: PIN LABELS Y AND Z ON TIMING, TEST, AND WAVEFORMS DIAGRAMS.
REFER TO PINS A AND B WHEN DE IS HIGH.
R
D
RO
DI
VCC
B
A
GND
8
7
6
5
1
2
3
4
DIP/SO
RE
DE
R
D
RO
DI
VCC
GND
8
7
6
5
1
2
3
4
RE
DE
D
R
DI
RO
MAX3070E–MAX3079E +3.3V, ±15kV ESD-Protected, Fail-Safe,
Hot-Swap, RS-485/RS-422 Transceivers
www.maximintegrated.com Maxim Integrated
│
20
Pin Congurations and Typical Operating Circuits
14
13
12
11
10
9
8
1
2
3
4
5
6
7
MAX3079E
MAX3079E
DIP/SO
TOP VIEW
VCC
VCC
RXP
TXP
A
B
Z
Y
RO
DE
DI
SRL
GND
RE
H/F
RO
TXP
A
B
Z
Y
GND DE SRL
DI
H/F
RXP
NOTE: SWITCH POSITIONS
INDICATED FOR H/F = GND.
RE
MAX3070E–MAX3079E +3.3V, ±15kV ESD-Protected, Fail-Safe,
Hot-Swap, RS-485/RS-422 Transceivers
www.maximintegrated.com Maxim Integrated
│
21
Pin Congurations and Typical Operating Circuits (continued)
†Devices are available in both leaded (Pb) and lead(Pb)-free
packaging. Specify lead-free by adding a “+” after the part
number.
PART† TEMP RANGE PIN-PACKAGE
MAX3070EEPD+ -40°C to +85°C 14 Plastic DIP
MAX3070EESD+ -40°C to +85°C 14 SO
MAX3070EAPD+ -40°C to +125°C 14 Plastic DIP
MAX3070EASD+ -40°C to +125°C 14 SO
MAX3071EEPA+ -40°C to +85°C 8 Plastic DIP
MAX3071EESA+ -40°C to +85°C 8 SO
MAX3071EAPA+ -40°C to +125°C 8 Plastic DIP
MAX3071EASA+ -40°C to +125°C 8 SO
MAX3072EEPA+ -40°C to +85°C 8 Plastic DIP
MAX3072EESA+ -40°C to +85°C 8 SO
MAX3072EAPA+ -40°C to +125°C 8 Plastic DIP
MAX3072EASA+ -40°C to +125°C 8 SO
MAX3073EEPD+ -40°C to +85°C 14 Plastic DIP
MAX3073EESD+ -40°C to +85°C 14 SO
MAX3073EAPD+ -40°C to +125°C 14 Plastic DIP
MAX3073EASD+ -40°C to +125°C 14 SO
MAX3074EEPA+ -40°C to +85°C 8 Plastic DIP
MAX3074EESA+ -40°C to +85°C 8 SO
MAX3074EAPA+ -40°C to +125°C 8 Plastic DIP
MAX3074EASA+ -40°C to +125°C 8 SO
MAX3075EEPA+ -40°C to +85°C 8 Plastic DIP
MAX3075EESA+ -40°C to +85°C 8 SO
MAX3077EESA/V+ -40°C to +85°C 8 SO
MAX3075EAPA+ -40°C to +125°C 8 Plastic DIP
MAX3075EASA+ -40°C to +125°C 8 SO
MAX3076EEPD+ -40°C to +85°C 14 Plastic DIP
MAX3076EESD+ -40°C to +85°C 14 SO
MAX3076EAPD+ -40°C to +125°C 14 Plastic DIP
MAX3076EASD+ -40°C to +125°C 14 SO
MAX3077EEPA+ -40°C to +85°C 8 Plastic DIP
MAX3077EESA+ -40°C to +85°C 8 SO
MAX3077EESA/V+ -40°C to +85°C 8 SO
MAX3077EAPA+ -40°C to +125°C 8 Plastic DIP
MAX3077EASA+ -40°C to +125°C 8 SO
MAX3077EMSA/PR+ -55°C to +125°C 8 SO
MAX3078EEPA+ -40°C to +85°C 8 Plastic DIP
MAX3078EESA+ -40°C to +85°C 8 SO
MAX3078EAPA+ -40°C to +125°C 8 Plastic DIP
MAX3078EASA+ -40°C to +125°C 8 SO
MAX3079EEPD+ -40°C to +85°C 14 Plastic DIP
MAX3079EESD+ -40°C to +85°C 14 SO
MAX3079EAPD+ -40°C to +125°C 14 Plastic DIP
MAX3079EASD+ -40°C to +125°C 14 SO
PACKAGE
TYPE
PACKAGE
CODE
OUTLINE
NO. LAND PATTERN NO.
8 Plastic P8+2 21-0043 —
14 Plastic P14+3
8 SO S8+4 21-0041 90-0096
14 SO S14+1 90-0112
MAX3070E–MAX3079E +3.3V, ±15kV ESD-Protected, Fail-Safe,
Hot-Swap, RS-485/RS-422 Transceivers
www.maximintegrated.com Maxim Integrated
│
22
Ordering Information Package Information
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.
REVISION
NUMBER
REVISION
DATE DESCRIPTION PAGES
CHANGED
0 10/02 Initial release. —
2 4/09 Added /PR information to reect new characterization information for military
temperature version.
2, 3, 7, 8, 12, 13, 19,
22–25
3 9/15 Updated Benets and Features section and added MAX3077EESA/V+ to Ordering
Information section for automotive customers 1, 22
4 1/16 Replaced leaded part numbers with lead-free part numbers 1, 18, 22
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 specications 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.
MAX3070E–MAX3079E +3.3V, ±15kV ESD-Protected, Fail-Safe,
Hot-Swap, RS-485/RS-422 Transceivers
© 2016 Maxim Integrated Products, Inc.
│
23
Revision History
For pricing, delivery, and ordering information, please contact Maxim Direct at 1-888-629-4642, or visit Maxim Integrated’s website at www.maximintegrated.com.
Mouser Electronics
Authorized Distributor
Click to View Pricing, Inventory, Delivery & Lifecycle Information:
Maxim Integrated:
MAX3070EAPD+ MAX3070EASD+ MAX3070EESD+ MAX3071EAPA+ MAX3071EASA+ MAX3071EEPA+
MAX3071EESA+ MAX3072EAPA+ MAX3072EASA+ MAX3072EEPA+ MAX3072EESA+ MAX3073EAPD+
MAX3073EASD+ MAX3073EEPD+ MAX3073EESD+ MAX3074EAPA+ MAX3074EASA+ MAX3074EEPA+
MAX3074EESA+ MAX3075EAPA+ MAX3075EASA+ MAX3075EEPA+ MAX3075EESA+ MAX3076EAPD+
MAX3076EASD+ MAX3076EEPD+ MAX3076EESD+ MAX3077EAPA+ MAX3077EASA+ MAX3077EEPA+
MAX3077EESA+ MAX3078EASA+ MAX3078EEPA+ MAX3078EESA+ MAX3079EAPD+ MAX3079EASD+
MAX3079EEPD+ MAX3079EESD+ MAX4582LESE+T MAX3070EASD+T MAX3070EESD+T MAX3071EASA+T
MAX3071EESA+T MAX3072EASA+T MAX3072EESA+T MAX3073EASD+T MAX3073EESD+T MAX3074EASA+T
MAX3074EESA+T MAX3075EASA+T MAX3075EESA+T MAX3076EASD+T MAX3076EESD+T MAX3077EASA+T
MAX3077EESA+T MAX3078EAPA+ MAX3078EASA+T MAX3078EESA+T MAX3079EASD+T MAX3079EESD+T
MAX3077EESA/V+ MAX3077EESA/V+T MAX3074EESA MAX3078EESA MAX3077EMSA/PR2 MAX3073EASD-T
MAX3073EASD