MAXIM MAX3061EEKA-T

19-2536; Rev 1; 7/07
±15kV ESD-Protected, Fail-Safe, 20Mbps, Slew-RateLimited RS-485/RS-422 Transceivers in a SOT
Features
The MAX3060E/MAX3061E/MAX3062E high-speed
transceivers for RS-485/RS-422 communication contain
one driver and one receiver. These devices feature failsafe circuitry, which guarantees a logic-high receiver
output when the receiver inputs are open or shorted.
This means that the receiver output is a logic high if all
transmitters on a terminated bus are disabled (high
impedance). These devices also feature hot-swap circuitry that eliminates data glitches during hot insertion.
The MAX3060E features slew-rate-limited drivers that
minimize EMI and reduce reflections caused by
improperly terminated cables, allowing error-free data
transmission up to 115kbps. The MAX3061E, also slewrate limited, transmits up to 500kbps. The MAX3062E
driver is not slew-rate limited, allowing transmit speeds
up to 20Mbps. All transmitter outputs are protected to
±15kV using the Human Body Model.
These transceivers typically draw 910µA of supply
current when unloaded, or 790µA when fully loaded
with the drivers disabled.
All devices have a 1/8-unit-load receiver input impedance that allows up to 256 transceivers on the bus. These
devices are intended for half-duplex communication.
Applications
♦ True Fail-Safe Receiver While Maintaining
EIA/TIA-485 Compatibility
♦ Enhanced Slew-Rate Limiting Facilitates
Error-Free Data Transmission (MAX3060E and
MAX3061E)
♦ 1nA Low-Current Shutdown Mode
♦ Hot-Swappable for Telecom Applications
♦ ESD Protection: ±15kV Human Body Model
♦ Allow Up to 256 Transceivers on the Bus
♦ Space-Saving 8-Pin SOT23 Package
Ordering Information
PART
TEMP RANGE
PINPACKAGE
TOP
MARK
MAX3060EEKA-T
-40°C to +85°C
8 SOT23-8
AAKI
MAX3060EEKA#T
-40°C to +85°C
8 SOT23-8
AEPA*
MAX3061EEKA-T
-40°C to +85°C
8 SOT23-8
AAKJ
MAX3061EEKA#T
-40°C to +85°C
8 SOT23-8
AEPB*
MAX3062EEKA-T
-40°C to +85°C
8 SOT23-8
AAKK
MAX3062EEKA#T
-40°C to +85°C
8 SOT23-8
AEPC*
*Indicates an RoHS-compliant part
T = Tape and Reel
RS-422/RS-485 Communications
Level Translators
Selector Guide
Transceivers for EMI-Sensitive Applications
Industrial-Control Local-Area Networks
PART
DATA
RATE
(Mbps)
SLEWRATE
LIMITED
TRANSCEIVERS
ON BUS
MAX3060E
0.115
Yes
256
MAX3061E
0.5
Yes
256
MAX3062E
20
No
256
Typical Operating Circuit/Pin Configuration
+5V
0.1μF
TOP VIEW
RO
1
R
RE 2
DE 3
DI 4
D
8 VCC
7 B
Rt
6
A
5 GND
MAX3060E
MAX3061E
MAX3062E
DE
D
DI
B
Rt
A
RO
R
RE
________________________________________________________________ Maxim Integrated Products
For pricing, delivery, and ordering information, please contact Maxim Direct at 1-888-629-4642,
or visit Maxim's website at www.maxim-ic.com.
1
MAX3060E/MAX3061E/MAX3062E
General Description
MAX3060E/MAX3061E/MAX3062E
±15kV ESD-Protected, Fail-Safe, 20Mbps, Slew-RateLimited RS-485/RS-422 Transceivers in a SOT
ABSOLUTE MAXIMUM RATINGS
All Voltages with Respect to GND
Supply Voltage (VCC) ............................................................+7V
Input Voltage (RE, DE, DI)..........................-0.3V to (VCC + 0.3V)
Driver Output/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 SOT23 (derate 8.9mW/°C above +70°C)............714mW
Operating Temperature Range
MAX306_EE_ _ ................................................-40°C to +85°C
Storage Temperature Range .............................-65°C to +150°C
Junction Temperature ......................................................+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.
DC ELECTRICAL CHARACTERISTICS
(VCC = +5V ±5%, TA = TMIN to TMAX, unless otherwise noted. Typical values are at VCC = +5V and TA = +25°C.) (Notes 1, 2)
PARAMETER
SYMBOL
CONDITIONS
MIN
TYP
MAX
UNITS
5
V
DRIVER
Differential Driver Output
(No Load)
VOD1
Differential Driver Output
VOD2
Change in Magnitude of
Differential Output Voltage
ΔVOD
Figure 1, R = 50Ω or R = 27Ω (Note 3)
Driver Common-Mode Output
Voltage
VOC
Figure 1, R = 50Ω or R = 27Ω
Change in Magnitude of
Common-Mode Voltage
ΔVOC
Figure 1, R = 50Ω or R = 27Ω (Note 3)
VCC = 5V
Figure 1, R = 50Ω (RS-422)
2.0
Figure 1, R = 27Ω (RS-485)
1.5
Input High Voltage
VIH
DE, DI, RE
Input Low Voltage
VIL
DE, DI, RE
DI Input Hysteresis
VHYS
Input Current
Hot-Swap Driver Input Current
Input Current (A and B)
Driver Short-Circuit Output
Current
ESD Protection for A, B
2
IIN1
IHOTSWAP
IIN2
VOD1
V
0.2
V
3
V
0.2
V
0.8
V
2.0
V
100
DE, DI, RE
DE, RE (Note 4)
DE = GND,
VCC = GND or 5.25V
VIN = +12V
VIN = -7V
-7V ≤ VOUT ≤ +12V, TA = +25°C (Note 5)
mV
±1
µA
±200
µA
125
-100
±15
±250
IEC 1000-4-2 Air-Gap Discharge
±7
IEC 1000-4-2 Contact Discharge
±7
Human Body Model
±15
_______________________________________________________________________________________
µA
mA
kV
±15kV ESD-Protected, Fail-Safe, 20Mbps, Slew-RateLimited RS-485/RS-422 Transceivers in a SOT
(VCC = +5V ±5%, TA = TMIN to TMAX, unless otherwise noted. Typical values are at VCC = +5V and TA = +25°C.) (Notes 1, 2)
PARAMETER
SYMBOL
CONDITIONS
MIN
TYP
MAX
UNITS
-200
-125
-50
mV
RECEIVER
Receiver Differential Threshold
Voltage
VTH
Receiver Input Hysteresis
ΔVTH
Receiver Output High Voltage
VOH
IO = -4mA, VID = -50mV
Receiver Output Low Voltage
VOL
IO = 4mA, VID = -200mV
Three-State Output Current at
Receiver
IOZR
0V ≤ VO ≤ VCC
Receiver Input Resistance
RIN
-7V ≤ VCM ≤ +12V
96
Receiver Output Short-Circuit
Current
IOSR
0V ≤ VRO ≤ VCC
±8
ICC
No load,
DI = GND or VCC
-7V ≤ VCM ≤ +12V
25
mV
VCC - 1.5
V
0.01
0.4
V
±1
µA
kΩ
±80
mA
SUPPLY CURRENT
Supply Current
Supply Current in Shutdown
Mode
ISHDN
DE = GND, RE = VCC
DE = RE = GND
790
1400
DE = RE = VCC
910
1500
0.001
1
µA
µA
_______________________________________________________________________________________
3
MAX3060E/MAX3061E/MAX3062E
DC ELECTRICAL CHARACTERISTICS (continued)
MAX3060E/MAX3061E/MAX3062E
±15kV ESD-Protected, Fail-Safe, 20Mbps, Slew-RateLimited RS-485/RS-422 Transceivers in a SOT
SWITCHING CHARACTERISTICS—MAX3060E
(VCC = +5V ±5%, TA = TMIN to TMAX, unless otherwise noted. Typical values are at VCC = +5V and TA = +25°C.) (Notes 1, 2)
PARAMETER
SYMBOL
CONDITIONS
MIN
TYP
MAX
UNITS
tDPLH, tDPHL
Figures 3 and 5, RDIFF = 54Ω,
CDIFF = 50pF
1.0
1.7
2.4
µs
Driver Output Skew
(tDPLH - tDPHL)
tDSKEW
Figures 3 and 5, RDIFF = 54Ω,
CDIFF = 50pF
-200
-7
+200
ns
Driver Rise or Fall Time
tDR, tDF
Figures 3 and 5, RDIFF = 54Ω,
CDIFF = 50pF
1.3
1.85
2.5
µs
Driver Input to Output
Maximum Data Rate
fMAX
Driver Enable to Output High
tDZH
Figures 4 and 6, CL = 100pF, S2 closed
0.6
1.5
Driver Enable to Output Low
tDZL
Figures 4 and 6, CL = 100pF, S1 closed
0.5
1.5
µs
Driver Disable Time from Low
tDLZ
Figures 4 and 6, CL = 15pF, S1 closed
60
200
ns
tDHZ
Driver Disable Time from High
115
kbps
µs
Figures 4 and 6, CL = 15pF, S2 closed
85
200
ns
Receiver Input to Output
tRPLH,
tRPHL
Figures 7 and 9; | VID | ≥ 2.0V;
rise and fall time of VID ≤ 4ns, CL = 15pF
47
80
ns
Differential Receiver Skew
(tRPLH - tRPHL)
tRSKD
Figures 7 and 9; | VID | ≥ 2.0V;
rise and fall time of VID ≤ 4ns, CL = 15pF
-3
+10
ns
-10
Receiver Enable to Output Low
tRZL
Figures 2 and 8, CL = 15pF, S1 closed
50
ns
Receiver Enable to Output High
tRZH
Figures 2 and 8, CL = 15pF, S2 closed
50
ns
Receiver Disable Time from Low
tRLZ
Figures 2 and 8, CL = 15pF, S1 closed
50
ns
tRHZ
Figures 2 and 8, CL = 15pF, S2 closed
Receiver Disable Time from High
Time to Shutdown
tSHDN
(Note 6)
50
180
50
ns
600
ns
Driver Enable from Shutdown to
Output High
tDZH(SHDN) Figures 4 and 6, CL = 100pF, S2 closed
2
µs
Driver Enable from Shutdown to
Output Low
tDZL(SHDN) Figures 4 and 6, CL = 100pF, S1 closed
2
µs
Receiver Enable from Shutdown
to Output High
tRZH(SHDN) Figures 2 and 8, CL = 15pF, S2 closed
1.5
µs
Receiver Enable from Shutdown
to Output Low
tRZL(SHDN) Figures 2 and 8, CL = 15pF, S1 closed
1.5
µs
4
_______________________________________________________________________________________
±15kV ESD-Protected, Fail-Safe, 20Mbps, Slew-RateLimited RS-485/RS-422 Transceivers in a SOT
MAX3060E/MAX3061E/MAX3062E
SWITCHING CHARACTERISTICS—MAX3061E
(VCC = +5V ±5%, TA = TMIN to TMAX, unless otherwise noted. Typical values are at VCC = +5V and TA = +25°C.) (Notes 1, 2)
PARAMETER
SYMBOL
CONDITIONS
MIN
TYP
MAX
UNITS
Driver Input to Output
tDPLH,
tDPHL
Figures 3 and 5, RDIFF = 54Ω,
CDIFF = 50pF
250
470
800
ns
Driver Output Skew
(tDPLH - tDPHL)
tDSKEW
Figures 3 and 5, RDIFF = 54Ω,
CDIFF = 50pF
-100
-4
+100
ns
Driver Rise or Fall Time
tDR, tDF
Figures 3 and 5, RDIFF = 54Ω,
CDIFF = 50pF
200
530
750
ns
Maximum Data Rate
fMAX
500
Driver Enable to Output High
tDZH
Figures 4 and 6, CL = 100pF, S2 closed
330
1000
ns
Driver Enable to Output Low
tDZL
Figures 4 and 6, CL = 100pF, S1 closed
200
1000
ns
Driver Disable Time from Low
tDLZ
Figures 4 and 6, CL = 15pF, S1 closed
60
200
ns
Driver Disable Time from High
tDHZ
Figures 4 and 6, CL = 15pF, S2 closed
80
200
ns
47
80
ns
-3
+10
ns
Receiver Input to Output
tRPLH,
tRPHL
Figures 7 and 9; | VID | ≥ 2.0V;
rise and fall time of VID ≤ 4ns, CL = 15pF
Differential Receiver Skew
(tRPLH - tRPHL)
tRSKD
Figures 7 and 9; | VID | ≥ 2.0V;
rise and fall time of VID ≤ 4ns, CL = 15pF
-10
kbps
Receiver Enable to Output Low
tRZL
Figures 2 and 8, CL = 15pF, S1 closed
50
ns
Receiver Enable to Output High
tRZH
Figures 2 and 8, CL = 15pF, S2 closed
50
ns
Receiver Disable Time from Low
tRLZ
Figures 2 and 8, CL = 15pF, S1 closed
50
ns
tRHZ
Figures 2 and 8, CL = 15pF, S2 closed
Receiver Disable Time from High
Time to Shutdown
tSHDN
(Note 6)
50
180
50
ns
600
ns
Driver Enable from Shutdown to
Output High
tDZH(SHDN
Figures 4 and 6, CL = 100pF, S2 closed
1.5
µs
Driver Enable from Shutdown to
Output Low
tDZL(SHDN) Figures 4 and 6, CL = 100pF, S1 closed
1.5
µs
Receiver Enable from Shutdown
to Output High
tRZH(SHDN) Figures 2 and 8, CL = 15pF, S2 closed
1.5
µs
Receiver Enable from Shutdown
to Output Low
tRZL(SHDN) Figures 2 and 8, CL = 15pF, S1 closed
1.5
µs
_______________________________________________________________________________________
5
MAX3060E/MAX3061E/MAX3062E
±15kV ESD-Protected, Fail-Safe, 20Mbps, Slew-RateLimited RS-485/RS-422 Transceivers in a SOT
SWITCHING CHARACTERISTICS—MAX3062E
(VCC = +5V ±5%, TA = TMIN to TMAX, unless otherwise noted. Typical values are at VCC = +5V and TA = +25°C.) (Notes 1, 2)
PARAMETER
SYMBOL
CONDITIONS
Driver Input to Output
tDPLH,
tDPHL
Figures 3 and 5, RDIFF = 54Ω,
CDIFF = 50pF
Driver Output Skew
(tDPLH - tDPHL)
tDSKEW
Figures 3 and 5, RDIFF = 54Ω,
CDIFF = 50pF
Driver Rise or Fall Time
tDR, tDF
Figures 3 and 5, RDIFF = 54Ω,
CDIFF = 50pF
MIN
-10
TYP
MAX
UNITS
20
30
ns
+1
+10
ns
8
15
ns
Maximum Data Rate
fMAX
Driver Enable to Output High
tDZH
Figures 4 and 6, CL = 100pF, S2 closed
250
500
ns
Driver Enable to Output Low
tDZL
Figures 4 and 6, CL = 100pF, S1 closed
250
500
ns
Driver Disable Time from Low
tDLZ
Figures 4 and 6, CL = 15pF, S1 closed
100
200
ns
tDHZ
Driver Disable Time from High
20
Mbps
Figures 4 and 6, CL = 15pF, S2 closed
100
200
ns
Receiver Input to Output
tRPLH,
tRPHL
Figures 7 and 9; | VID | ≥ 2.0V;
rise and fall time of VID ≤ 4ns, CL = 15pF
45
80
ns
Differential Receiver Skew
(tRPLH - tRPHL)
tRSKD
Figures 7 and 9; | VID | ≥ 2.0V;
rise and fall time of VID ≤ 4ns, CL = 15pF
-4
+10
ns
-10
Receiver Enable to Output Low
tRZL
Figures 2 and 8, CL = 15pF, S1 closed
50
ns
Receiver Enable to Output High
tRZH
Figures 2 and 8, CL = 15pF, S2 closed
50
ns
Receiver Disable Time from Low
tRLZ
Figures 2 and 8, CL = 15pF, S1 closed
50
ns
tRHZ
Figures 2 and 8, CL = 15pF, S2 closed
Receiver Disable Time from High
Time to Shutdown
tSHDN
(Note 6)
50
180
50
ns
600
ns
Driver Enable from Shutdown to
Output High
tDZH(SHDN) Figures 4 and 6, CL = 100pF, S2 closed
100
ns
Driver Enable from Shutdown to
Output Low
tDZL(SHDN) Figures 4 and 6, CL = 100pF, S1 closed
100
ns
Receiver Enable from Shutdown
to Output High
tRZH(SHDN) Figures 2 and 8, CL = 15pF, S2 closed
1.5
µs
Receiver Enable from Shutdown
to Output Low
tRZL(SHDN) Figures 2 and 8, CL = 15pF, S1 closed
1.5
µs
Note 1: Overtemperature limits are guaranteed by design and are not production tested. Devices are tested at TA = +25°C.
Note 2: 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 3: ΔVOD and ΔVOC are the changes in VOD and VOC, respectively, when the DI input changes state.
Note 4: This input current level is for the hot-swap enable (DE, RE) inputs and is present until the first transition only. After the first
transition, the input reverts to a standard high-impedance CMOS input with input current IIN1. For the first 10µs, the input
current can be as high as 1mA. During this period the input is disabled.
Note 5: Maximum current level applies to peak current just prior to foldback-current limiting; minimum current level applies during
current limiting.
Note 6: The device is put into shutdown by bringing RE high and DE low. 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 600ns, the device is guaranteed
to have entered shutdown.
6
_______________________________________________________________________________________
±15kV ESD-Protected, Fail-Safe, 20Mbps, Slew-RateLimited RS-485/RS-422 Transceivers in a SOT
MAX3060E/MAX3061E/MAX3062E
A
R
RECEIVER
OUTPUT
1kΩ
TEST POINT
VCC
S1
CL
15pF
VOD2
R
1kΩ
VOC
S2
B
Figure 2. Receiver Enable/Disable Timing Test Load
Figure 1. Driver DC Test Load
5V
DE
DI
A
VOD2
RDIFF
VCC
S1
500Ω
OUTPUT
UNDER TEST
CDIFF
B
CL
S2
Figure 3. Driver Timing Test Circuit
Figure 4. Driver Enable/Disable Timing Test Load
5V
DI
1.5V
0
5V
1.5V
tDPLH
DE
tDPHL
tDLZ
A, B
A
VO
0
-VO
1.5V
tDZL(SHDN), tDZL
B
VDIFF
1.5V
0
VOL
2.3V OUTPUT NORMALLY LOW
VDIFF = V (A) - V (B)
10%
tDR
90%
90%
tDF
tDSKEW = | tDPLH - tDPHL |
Figure 5. Driver Propagation Delays
OUTPUT NORMALLY HIGH
A, B
10%
VOL + 0.5V
VOH - 0.5V
2.3V
0
tDZH(SHDN), tDZH
tDHZ
Figure 6. Driver Enable and Disable Times
_______________________________________________________________________________________
7
5V
RE
1.5V
1.5V
0
RO
VOH
A
-1V
B
tRLZ
tRZL(SHDN), tRZL
1.5V
VOL
1V
tRPHL
VCC
RO
1.5V
OUTPUT
1.5V OUTPUT NORMALLY LOW
VOL + 0.5V
tRPLH
OUTPUT NORMALLY HIGH
INPUT
RO
VOH - 0.5V
1.5V
0
tRZH(SHDN), tRZH
Figure 7. Receiver Propagation Delays
tRHZ
Figure 8. Receiver Enable and Disable Times
B
VID
ATE
RECEIVER
OUTPUT
RR
A
Figure 9. Receiver Propagation Delay Test Circuit
Typical Operating Characteristics
(VCC = +5V, TA = +25°C, unless otherwise noted.)
850
DE = RE = GND
750
40
30
20
700
10
650
0
18
16
OUTPUT CURRENT (mA)
50
OUTPUT CURRENT (mA)
900
20
MAX3060E toc02
DE = RE = VCC
800
60
MAX3060E toc01
950
RECEIVER OUTPUT CURRENT
vs. RECEIVER OUTPUT HIGH VOLTAGE
RECEIVER OUTPUT CURRENT
vs. RECEIVER OUTPUT LOW VOLTAGE
MAX3060E toc03
NO-LOAD SUPPLY CURRENT
vs. TEMPERATURE
NO-LOAD SUPPLY CURRENT (μA)
MAX3060E/MAX3061E/MAX3062E
±15kV ESD-Protected, Fail-Safe, 20Mbps, Slew-RateLimited RS-485/RS-422 Transceivers in a SOT
14
12
10
8
6
4
2
-40
-15
10
35
TEMPERATURE (°C)
8
60
85
0
0
1
2
3
OUTPUT LOW VOLTAGE (V)
4
5
0
1
2
3
OUTPUT HIGH VOLTAGE (V)
_______________________________________________________________________________________
4
5
±15kV ESD-Protected, Fail-Safe, 20Mbps, Slew-RateLimited RS-485/RS-422 Transceivers in a SOT
3.0
2.5
2.0
1.5
1.0
0.35
0.30
0.25
0.20
IRO = -8mA
4.0
3.8
3.6
3.4
0
3.2
0.10
-40
-15
10
35
60
85
-40
-15
10
35
60
-40
85
-15
10
35
60
TEMPERATURE (°C)
TEMPERATURE (°C)
RECEIVER PROPAGATION DELAY
(MAX3060E/MAX3061E) vs. TEMPERATURE
RECEIVER PROPAGATION DELAY
(MAX3062E) vs. TEMPERATURE
DRIVER PROPAGATION DELAY
(MAX3060E) vs. TEMPERATURE
50
45
40
35
CL = 15pF
65
60
55
50
45
40
35
1.80
1.76
1.74
1.72
1.70
1.68
1.66
30
30
1.64
25
25
1.62
20
20
-15
10
35
60
1.60
-40
85
-15
10
35
60
85
-15
10
35
60
85
TEMPERATURE (°C)
TEMPERATURE (°C)
DRIVER PROPAGATION DELAY
(MAX3061E) vs. TEMPERATURE
DRIVER PROPAGATION DELAY
(MAX3062E) vs. TEMPERATURE
DRIVER DIFFERENTIAL OUTPUT VOLTAGE
vs. TEMPERATURE
520
500
480
460
440
30
Rt = 54Ω
25
20
15
10
5
420
-15
10
35
TEMPERATURE (°C)
60
85
Rt = 54Ω
3.2
3.0
2.8
2.6
2.4
2.2
2.0
0
400
3.4
MAX3060E toc12
Rt = 54Ω
OUTPUT VOLTAGE (V)
MAX3060E toc10
540
-40
-40
TEMPERATURE (°C)
PROPAGATION DELAY (ns)
-40
Rt = 54Ω
1.78
PROPAGATION DEALY (μs)
55
MAX3060E toc08
60
70
PROPAGATION DEALY (ns)
MAX3060E toc07
CL = 15pF
65
85
MAX3060E toc09
TEMPERATURE (°C)
70
PROPAGATION DEALY (ns)
0.40
4.2
0.15
0.5
PROPAGATION DELAY (ns)
IRO = 8mA
0.45
OUTPUT HIGH VOLTAGE (V)
3.5
MAX3060E toc05
4.0
0.50
MAX3060E toc11
SHUTDOWN CURRENT (nA)
4.5
OUTPUT LOW VOLTAGE (V)
MAX3060E toc04
5.0
RECEIVER OUTPUT HIGH VOLTAGE
vs. TEMPERATURE
RECEIVER OUTPUT LOW VOLTAGE
vs. TEMPERATURE
MAX3060E toc06
SHUTDOWN CURRENT
vs. TEMPERATURE
-40
-15
10
35
TEMPERATURE (°C)
60
85
-40
-15
10
35
60
85
TEMPERATURE (°C)
_______________________________________________________________________________________
9
MAX3060E/MAX3061E/MAX3062E
Typical Operating Characteristics (continued)
(VCC = +5V, TA = +25°C, unless otherwise noted.)
Typical Operating Characteristics (continued)
(VCC = +5V, TA = +25°C, unless otherwise noted.)
DRIVER OUTPUT CURRENT
vs. OUTPUT LOW VOLTAGE
1
0.1
MAX3060E toc14
120
80
70
DRIVER OUTPUT CURRENT (mA)
10
90
DRIVER OUTPUT CURRENT (mA)
MAX3060E toc13
100
DRIVER OUTPUT CURRENT
vs. OUTPUT HIGH VOLTAGE
60
50
40
30
20
MAX3060E toc15
DRIVER OUTPUT CURRENT
vs. DIFFERENTIAL OUTPUT VOLTAGE
OUTPUT CURRENT (mA)
MAX3060E/MAX3061E/MAX3062E
±15kV ESD-Protected, Fail-Safe, 20Mbps, Slew-RateLimited RS-485/RS-422 Transceivers in a SOT
100
80
60
40
20
10
0.01
0
0
0
1
2
3
4
5
6
0
DIFFERENTIAL OUTPUT VOLTAGE (V)
2
4
6
8
10
12
-8
OUTPUT LOW VOLTAGE (V)
RECEIVER PROPAGATION DELAY
(MAX3060E/MAX3061E)
-4
-2
0
2
4
6
OUTPUT HIGH VOLTAGE (V)
DRIVER PROPAGATION DELAY
(MAX3061E)
RECEIVER PROPAGATION DELAY
(MAX3062E)
MAX3060E toc16
-6
MAX3060E toc18
MAX3060E toc17
DI
5V/div
VA - V B
1V/div
VA - V B
1V/div
RO
5V/div
RO
5V/div
VA - VB
2V/div
20ns/div
20ns/div
1μs/div
DRIVER PROPAGATION DELAY
(MAX3060E)
DRIVER PROPAGATION DELAY
(MAX3061E)
DRIVER PROPAGATION DELAY
(MAX3062E)
MAX3060E toc20
MAX3060E toc19
MAX3060E toc21
DI
5V/div
DI
5V/div
VA - V B
2V/div
VA - VB
2V/div
2μs/div
10
10ns/div
20ns/div
______________________________________________________________________________________
±15kV ESD-Protected, Fail-Safe, 20Mbps, Slew-RateLimited RS-485/RS-422 Transceivers in a SOT
PIN
NAME
FUNCTION
1
RO
Receiver Output. When RE is low and when A - B ≥ -50mV, RO is high; if A - B ≤ -200mV, RO is low. RO
is high impedance when RE is high.
2
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 and reverts to a standard
CMOS input after the first low transition.
3
DE
Driver Output Enable. Drive DE high to enable driver outputs. Driver 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 and
reverts to a standard CMOS input after the first high transition.
4
DI
Driver Input. With DE high, a low on DI forces the noninverting output low and the inverting output high.
Similarly, a high on DI forces the noninverting output high and the inverting output low.
5
GND
6
A
Noninverting Receiver Input and Noninverting Driver Output
7
B
Inverting Receiver Input and Inverting Driver Output
8
VCC
Ground
Positive Supply. Bypass with a 0.1µF capacitor to GND.
Detailed Description
The MAX3060E/MAX3061E/MAX3062E 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). All devices
have a hot-swap input structure that prevents disturbances on the differential signal lines when a circuit
board is plugged into a hot backplane (see the Hot-Swap
Capability section). The MAX3060E features a reduced
slew-rate driver that minimizes EMI and reduces reflections caused by improperly terminated cables, allowing
error-free data transmission up to 115kbps (see the
Reduced EMI and Reflections section). The MAX3061E is
also slew-rate limited, transmitting up to 500kbps. The
MAX3062E driver is not slew-rate limited, allowing transmit speeds up to 20Mbps. The MAX3060E/MAX3061E/
MAX3062E are half-duplex transceivers.
All of these parts operate from a single +5V supply.
Drivers are output short-circuit current limited. Thermalshutdown circuitry protects drivers against excessive
power dissipation. When activated, the thermal-shutdown circuitry places the driver outputs into a highimpedance state.
Receiver Input Filtering
The receivers of the MAX3060E and MAX3061E 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 2ns due to this filtering.
Fail-Safe
The MAX3060E family of devices guarantee 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 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. In the case of an unterminated bus
with all transmitters disabled, the receiver’s differential
input voltage is pulled to 0V by the receiver’s input resistors. With the receiver thresholds of the MAX3060E family, this results in a logic high output with a 50mV
minimum input noise margin. Unlike previous fail-safe
devices, the -50mV to -200mV threshold complies with
the ±200mV EIA/TIA-485 standard.
______________________________________________________________________________________
11
MAX3060E/MAX3061E/MAX3062E
Pin Description
MAX3060E/MAX3061E/MAX3062E
±15kV ESD-Protected, Fail-Safe, 20Mbps, Slew-RateLimited RS-485/RS-422 Transceivers in a SOT
Functional Tables
Table 2. Receiver Functional Table
Table 1. Transmitter Functional Table
TRANSMITTING
RECEIVING
INPUTS
OUTPUTS
INPUTS
OUTPUT
RO
RE
DE
DI
B
A
RE
DE
A-B
X
1
1
0
1
0
X
≥ -0.05V
1
0
X
1
0
1
0
0
X
≤ -0.2V
0
0
X
High-Z
High-Z
0
X
Open/shorted
1
1
0
X
1
1
X
High-Z
1
0
X
Shutdown
Shutdown*
X = Don’t care.
*Shutdown mode, driver and receiver outputs are high impedance.
Hot-Swap Capability
Hot-Swap Input
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 powerup sequence. During this period, the processor’s logicoutput drivers are high impedance and are unable to
drive the DE and RE inputs of the MAX306_E to a defined
logic level. Leakage currents up to ±10µA from the highimpedance 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 for at least 10µs and until the current into DE
exceeds 200µA. After the initial positive transition, the
pulldown circuit becomes transparent, resetting the
hot-swap tolerable input.
Hot-Swap Input Circuitry
These devices’ enable inputs feature hot-swap capability. At the input there are two NMOS devices, M1 and M2
(Figure 10). 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 300µA current sink, and M1, a
30µA current sink, pull DE to GND through an 8kΩ 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 threestate leakages that can drive DE high. M1 remains on
12
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, highimpedance 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.
VCC
10μs
TIMER
SR LATCH
TIMER
8kΩ
DE
(HOT SWAP)
DE
30μA
M1
300μA
M2
Figure 10. Simplified Structure of the Driver Enable Input (DE)
______________________________________________________________________________________
±15kV ESD-Protected, Fail-Safe, 20Mbps, Slew-RateLimited RS-485/RS-422 Transceivers in a SOT
MAX3060E/MAX3061E/MAX3062E
Hot-Swap Line Transient
The circuit of Figure 11 shows a typical offset termination used to guarantee a greater than 200mV offset
when a line is not driven (the 50pF represents the minimum parasitic capacitance that would exist in a typical
application). During a hot-swap event when the driver
is connected to the line and is powered up, the driver
must not cause the differential signal to drop below
200mV. Figures 12, 13, and 14 show the results of the
MAX3060E during power-up for three different V CC
ramp rates (0.1V/µs, 1V/µs, and 10V/µs). The photos
show the VCC ramp, the single-ended signal on each
side of the 100Ω termination, as well as the differential
signal across the termination.
5V
0
VCC
A
200mV/div
B
200mV/div
238mV
20mV/div
A-B
40μs/div
±15kV ESD Protection
As with all Maxim devices, ESD-protection structures
are incorporated on all pins to protect against ESD
encountered during handling and assembly. The
MAX3060E family’s receiver inputs/driver outputs (A, B)
have extra protection against static electricity found in
normal operation. Maxim’s engineers developed stateof-the-art structures to protect these pins against
±15kV ESD without damage. After an ESD event, the
devices continue working without latchup.
ESD protection can be tested in several ways. The
receiver inputs are characterized for protection to the
following:
• ±15kV using the Human Body Model
• ±7kV using the Contact Discharge method specified
in IEC 1000-4-2 (formerly IEC 801-2)
• ±7kV using the Air-Gap Discharge method specified
in IEC 1000-4-2 (formerly IEC 801-2)
Figure 12. Differential Power-Up Glitch (0.1V/µs)
5V
VCC
0
A
20mV/div
B
20mV/div
238mV
20mV/div
A-B
2μs/div
Figure 13. Differential Power-Up Glitch (1V/µs)
5.0V
5V
VCC
0
1kΩ
VCC
A
DI
VCC OR GND
A
0.1kΩ
50mV/div
50pF
B
50mV/div
B
1kΩ
238mV
20mV/div
A-B
200ns/div
Figure 11. Typical Offset Termination
Figure 14. Differential Power-Up Glitch (10V/µs)
______________________________________________________________________________________
13
MAX3060E/MAX3061E/MAX3062E
±15kV ESD-Protected, Fail-Safe, 20Mbps, Slew-RateLimited RS-485/RS-422 Transceivers in a SOT
ESD Test Conditions
ESD performance depends on a number of conditions.
Contact Maxim for a reliability report that documents
test setup, methodology, and results.
Human Body Model
Figure 15a shows the Human Body Model, and Figure
15b 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 device through a
1.5kΩ resistor.
IEC 1000-4-2
The IEC 1000-4-2 standard covers ESD testing and performance of finished equipment; it does not specifically
refer to integrated circuits.
The main 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 ESD test model (Figure 16), the
ESD withstand voltage measured to this standard is generally lower than that measured using the Human Body
Model. 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 testing uses a 200pF storage capacitor and zero-discharge resistance. It mimics
the stress caused by handling during manufacturing
and assembly. All pins (not just RS-485 inputs) require
this protection during manufacturing. Therefore, the
Machine Model is less relevant to the I/O ports than are
the Human Body Model and IEC 1000-4-2.
RC
1MΩ
CHARGE-CURRENT
LIMIT RESISTOR
HIGHVOLTAGE
DC
SOURCE
The standard RS-485 receiver input impedance is 12kΩ
(one-unit load), and the standard driver can drive up to
32-unit loads. The MAX3060E family of transceivers have
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 and/or other RS-485 transceivers with a total of
32 unit loads or less can be connected to the line.
Reduced EMI and Reflections
The MAX3060E and MAX3061E are slew-rate limited,
minimizing EMI and reducing reflections caused by
improperly terminated cables. Figure 17 shows the driver output waveform and its Fourier analysis of a 25kHz
14
DISCHARGE
RESISTANCE
DEVICE
UNDER
TEST
STORAGE
CAPACITOR
Figure 15a. Human Body ESD Test Model
IP 100%
90%
Ir
PEAK-TO-PEAK RINGING
(NOT DRAWN TO SCALE)
AMPERES
36.8%
10%
0
0
tRL
TIME
tDL
CURRENT WAVEFORM
Figure 15b. Human Body Current Waveform
RC
50MΩ to 100MΩ
CHARGE-CURRENT
LIMIT RESISTOR
Applications Information
256 Transceivers on the Bus
Cs
100pF
RD
1.5kΩ
HIGHVOLTAGE
DC
SOURCE
Cs
150pF
RD
330Ω
DISCHARGE
RESISTANCE
STORAGE
CAPACITOR
DEVICE
UNDER
TEST
Figure 16. IEC 1000-4-2 ESD Test Model
signal transmitted by a MAX3062E. High-frequency
harmonic components with large amplitudes are evident. Figure 18 shows the same signal displayed for a
MAX3061E transmitting under the same conditions.
______________________________________________________________________________________
±15kV ESD-Protected, Fail-Safe, 20Mbps, Slew-RateLimited RS-485/RS-422 Transceivers in a SOT
For example, the MAX3060E’s rise time is typically
1850ns, which results in excellent waveforms with a stub
length up to 123ft. A system can work well with longer
unterminated stubs, even with severe reflections, if the
waveform settles out before the UART samples them.
20dB/div
0
125kHz/div
1.25MHz
Figure 17. Driver Output Waveform and FFT Plot of MAX3062E
Transmitting a 25kHz Signal
Low-Power Shutdown Mode
Low-power shutdown mode is initiated by bringing both
RE high and DE low. In shutdown, the devices typically
draw only 1nA 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 t_ ZH and t_ ZL in the Switching Characteristics tables assume the part was not in a lowpower shutdown state. Enable times t_ZH(SHDN) and
t_ZL(SHDN) assume the parts were shut down. It takes
drivers and receivers longer to become enabled from
low-power shutdown mode (t_ZH(SHDN), t_ZL(SHDN))
than from driver/receiver-disable mode (t_ZH, t_ZL).
20dB/div
0
125kHz/div
1.25MHz
Figure 18. Driver Output Waveform and FFT Plot of MAX3061E
Transmitting a 25kHz Signal
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 protection after a 20µs delay against
short circuits over the whole common-mode voltage
range (see Typical Operating Characteristics). The second, a thermal shutdown circuit, forces the driver outputs into a high-impedance state if the die temperature
becomes excessive.
20dB/div
0
125kHz/div
1.25MHz
Figure 19. Driver Output Waveform and FFT Plot of MAX3060E
Transmitting a 25kHz Signal
______________________________________________________________________________________
15
MAX3060E/MAX3061E/MAX3062E
Figure 18’s high-frequency harmonic components are
much lower in amplitude, compared with Figure 17’s,
and the potential for EMI is significantly reduced. Figure
19 shows the same signal displayed for a MAX3060E
transmitting under the same conditions. Figure 19’s
high-frequency harmonic components are even lower.
In general, a transmitter’s rise time relates directly to the
length of an unterminated stub, which can be driven with
only minor waveform reflections. The following equation
expresses this relationship conservatively:
Length = tRISE / (10 x 1.5ns/ft)
where tRISE is the transmitter’s rise time.
MAX3060E/MAX3061E/MAX3062E
±15kV ESD-Protected, Fail-Safe, 20Mbps, Slew-RateLimited RS-485/RS-422 Transceivers in a SOT
120Ω
120Ω
DI
DE
B
B
D
D
DI
DE
RO
RE
A
B
A
B
A
A
R
R
RO
RE
R
R
D
D
MAX3060E/MAX3061E/
MAX3062E
(HALF-DUPLEX)
DI
DE
RO RE
DI
DE
RO RE
Figure 20. Typical Half-Duplex RS-485 Network
Typical Applications
The MAX3060E family of transceivers are designed for
bidirectional data communications on multipoint bus
transmission lines. Figure 20 shows a typical network
application circuit.
Chip Information
PROCESS: CMOS
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 MAX3060E and
MAX3061E are more tolerant of imperfect termination.
16
______________________________________________________________________________________
±15kV ESD-Protected, Fail-Safe, 20Mbps, Slew-RateLimited RS-485/RS-422 Transceivers in a SOT
SOT23, 8L.EPS
MARKING
0
0
PACKAGE OUTLINE, SOT-23, 8L BODY
21-0078
G
1
1
Revision History
Pages changed at Rev 1: 1, 16, 17
Maxim cannot assume responsibility for use of any circuitry other than circuitry entirely embodied in a Maxim product. No circuit patent licenses are
implied. Maxim reserves the right to change the circuitry and specifications without notice at any time.
Maxim Integrated Products, 120 San Gabriel Drive, Sunnyvale, CA 94086 408-737-7600 ____________________ 17
© 2007 Maxim Integrated Products
is a registered trademark of Maxim Integrated Products, Inc.
MAX3060E/MAX3061E/MAX3062E
Package Information
(The package drawing(s) in this data sheet may not reflect the most current specifications. For the latest package outline information
go to www.maxim-ic.com/packages.)