MAX3488EESA-T [MAXIM]
Line Transceiver, 1 Func, 1 Driver, 1 Rcvr, CMOS, PDSO8, SO-8;
| 型号： | MAX3488EESA-T |
| 厂家： | 
MAXIM INTEGRATED PRODUCTS |
| 描述： | Line Transceiver, 1 Func, 1 Driver, 1 Rcvr, CMOS, PDSO8, SO-8 光电二极管 |
| 文件： | 总16页 (文件大小：176K) |
| 中文： | 中文翻译 | 下载： | 下载PDF数据表文档文件 |
19-1474; Rev 0; 4/99
3.3V-Pow e re d, ±15kV ESD-Prote c te d, 12Mbps a nd
Sle w -Ra te -Lim ite d True RS -485/RS -422 Tra ns c e ive rs
5680/MAX3491E
Ge n e ra l De s c rip t io n
Fe a t u re s
Devices in the MAX3483E family (MAX3483E/MAX3485E/
MAX3486E/MAX3488E/MAX3490E/MAX3491E) a re
±15kV ESD-protected, +3.3V, low-power transceivers for
RS-485 and RS-422 communications. Each device con-
tains one driver and one receiver. The MAX3483E and
MAX3488E feature slew-rate-limited drivers that minimize
EMI and reduce reflections caused by improperly termi-
nated 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)
All devices feature enhanced electrostatic discharge
(ESD) protection. All transmitter outputs and receiver
inputs are protected to ±15kV using IEC 1000-4-2 Air-
Ga p Dis c ha rg e , ± 8kV us ing IEC 1000-4-2 Conta c t
Discharge, and ±15kV using the Human Body Model.
♦ Slew-Rate Limited for Errorless Data Transmission
(MAX3483E/MAX3488E)
♦ 2nA Low-Current Shutdown Mode
(MAX3483E/MAX3485E/MAX3486E/MAX3491E)
Drivers are short-circuit current limited and are protect-
ed 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
fe a ture tha t g ua ra nte e s a log ic -hig h outp ut if b oth
inputs are open circuit.
♦ -7V to +12V Common-Mode Input Voltage Range
♦ Full-Duplex and Half-Duplex Versions Available
♦ Industry-Standard 75176 Pinout
(MAX3483E/MAX3485E/MAX3486E)
♦ Current-Limiting and Thermal Shutdown for
The MAX3488E, MAX3490E, and MAX3491E feature
full-d up le x c ommunic a tion, while the MAX3483E,
MAX3485E, a nd MAX3486E a re d e s ig ne d for ha lf-
duplex communication.
Driver Overload Protection
Ord e rin g In fo rm a t io n
PART
TEMP. RANGE
0°C to +70°C
0°C to +70°C
-40°C to +85°C
-40°C to +85°C
0°C to +70°C
0°C to +70°C
-40°C to +85°C
-40°C to +85°C
PIN-PACKAGE
8 SO
MAX3483ECSA
MAX3483ECPA
MAX3483EESA
MAX3483EEPA
MAX3485ECSA
MAX3485ECPA
MAX3485EESA
MAX3485EEPA
Ap p lic a t io n s
Telecommunications
8 Plastic DIP
8 SO
Industrial-Control Local Area Networks
Transceivers for EMI-Sensitive Applications
Integrated Services Digital Networks
Packet Switching
8 Plastic DIP
8 SO
8 Plastic DIP
8 SO
8 Plastic DIP
Ordering Information continued at end of data sheet.
S e le c t o r Gu id e
GUARANTEED SUPPLY
DRIVER/ SHUTDOWN
RECEIVER CURRENT
±15kV
ESD
PROTECTION
PART
NUMBER
HALF/FULL SLEW-RATE
PIN
COUNT
DATA RATE
(Mbps)
VOLTAGE
(V)
DUPLEX
LIMITED
ENABLE
(nA)
MAX3483E
MAX3485E
MAX3486E
MAX3488E
MAX3490E
MAX3491E
0.25
12
Half
Half
Half
Full
Full
Full
Yes
No
Yes
Yes
Yes
No
2
2
Yes
Yes
Yes
Yes
Yes
Yes
8
8
2.5
0.25
12
Yes
Yes
No
2
8
3.0 to 3.6
—
—
2
8
No
8
12
No
Yes
14
________________________________________________________________ Maxim Integrated Products
1
For free samples & the latest literature: http://www.maxim-ic.com, or phone 1-800-998-8800.
For small orders, phone 1-800-835-8769.
3.3V-Pow e re d, ±15kV ESD-Prote c te d, 12Mbps a nd
Sle w -Ra te -Lim ite d True RS -485/RS -422 Tra ns c e ive rs
ABSOLUTE MAXIMUM RATINGS
Supply Voltage (V ).............................................................+7V
CC
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
Storage Temperature Range .............................-65°C to +150°C
Lead Temperature (soldering, 10sec) .............................+300°C
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 (V + 0.3V)
CC
Continuous Power Dissipation (T = +70°C)
A
8-Pin SO (derate 5.88mW/°C above +70°C)..................471mW
8-Pin Plastic DIP (derate 9.09mW/°C above +70°C) .....727mW
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
(V = +3.3V ±0.3V, T = T
to T , unless otherwise noted. Typical values are at T = +25°C.)
MAX A
CC
A
MIN
PARAMETER
SYMBOL
CONDITIONS
= 100Ω (RS-422), Figure 4
= 54Ω (RS-485), Figure 4
MIN
2.0
1.5
1.5
TYP
MAX
UNITS
R
L
R
L
R
L
Differential Driver Output
V
OD
V
= 60Ω (RS-485), V = 3.3V, Figure 5
CC
Change in Magnitude of Driver
Differential Output Voltage for
Complementary Output States
(Note 1)
∆V
R
L
= 54Ω or 100Ω, Figure 4
0.2
V
OD
Driver Common-Mode Output
Voltage
V
R
R
= 54Ω or 100Ω, Figure 4
= 54Ω or 100Ω, Figure 4
3
V
V
OC
L
Change in Magnitude of
Common-Mode Output Voltage
(Note 1)
∆V
0.2
OC
L
Input High Voltage
Input Low Voltage
Logic Input Current
V
2.0
V
V
DE, DI, RE
DE, DI, RE
DE, DI, RE
DE = 0,
IH
V
IL
0.8
I
IN1
±2
1.0
-0.8
20
µA
V
= 12V
= -7V
IN
Input Current (A, B)
I
IN2
mA
µA
µA
V
V
CC
= 0 or 3.6V
V
IN
V
OUT
= 12V
DE = 0, RE = 0,
= 0 or 3.6V, MAX3491E
Output Leakage (Y, Z)
I
O
V
V
OUT
= -7V
= 12V
= -7V
-20
1
CC
V
OUT
Output Leakage (Y, Z)
in Shutdown Mode
DE = 0, RE = V
,
CC
I
O
V
CC
= 0 or 3.6V, MAX3491E
V
OUT
-1
Receiver Differential
Threshold Voltage
V
TH
-7V ≤ V ≤ 12V
-0.2
0.2
CM
Receiver Input Hysteresis
∆V
V
= 0
50
mV
V
TH
CM
Receiver Output High Voltage
Receiver Output Low Voltage
V
OH
I
= -1.5mA, V = 200mV, Figure 6
V
CC
- 0.4
OUT
ID
V
OL
I
= 2.5mA, V = 200mV, Figure 6
0.4
±1
V
OUT
ID
Three-State (High-Impedance)
Output Current at Receiver
I
V
CC
= 3.6V, 0 ≤ V
≤ V
CC
µA
OZR
OUT
Receiver Input Resistance
Supply Voltage Range
R
-7V ≤ V ≤ 12V
12
3.0
kΩ
IN
CM
V
CC
3.6
2.2
1.9
1
V
1.1
0.95
0.002
DE = V , RE = 0 or V
CC
CC
No load,
Supply Current
I
CC
mA
µA
DI = 0 or V
CC
DE = 0, RE = 0
Supply Current in Shutdown Mode
I
SHDN
DE = 0, RE = V , DI = V or 0
CC
CC
5680/MAX3491E
2
_______________________________________________________________________________________
3.3V-Pow e re d, ±15kV ESD-Prote c te d, 12Mbps a nd
Sle w -Ra te -Lim ite d True RS -485/RS -422 Tra ns c e ive rs
5680/MAX3491E
DC ELECTRICAL CHARACTERISTICS (continued)
(V = +3.3V ±0.3V, T = T
to T , unless otherwise noted. Typical values are at T = +25°C.)
MAX A
CC
A
MIN
PARAMETER
SYMBOL
CONDITIONS
MIN
TYP
MAX
-250
250
UNITS
mA
V
= -7V
= 12V
OUT
Driver Short-Circuit Output Current
I
OSD
V
OUT
Receiver Short-Circuit Output Current
ESD Protection for Y, Z, A, B
I
0 ≤ V ≤ V
CC
±8
±60
mA
OSR
RO
IEC 1000-4-2 Air Discharge
±15
±8
IEC 1000-4-2 Contact Discharge
(MAX3483E, MAX3485E,
MAX3486E, MAX3491E)
kV
IEC 1000-4-2 Contact Discharge
(MAX3490E, MAX3488E)*
±6
Human Body Model
±15
*MAX3488E and MAX3491E will be compliant to ±8kV per IEC 1000-4-2 Contact Discharge by September 1999.
DRIVER SWITCHING CHARACTERISTICS—MAX3485E/MAX3490E/MAX3491E
(V = +3.3V, T = +25°C.)
CC
A
PARAMETER
SYMBOL
CONDITIONS
MIN
12
1
TYP
15
MAX
UNITS
Mbps
ns
Maximum Data Rate
Driver Differential Output Delay
t
R
R
R
R
R
= 60Ω, Figure 7
= 60Ω, Figure 7
= 27Ω, Figure 8
= 27Ω, Figure 8
= 27Ω, Figure 8
22
35
25
35
35
±8
DD
L
L
L
L
L
Driver Differential Output Transition Time
Driver Propagation Delay, Low-to-High Level
Driver Propagation Delay, High-to-Low Level
t
TD
3
11
ns
t
t
t
7
23
ns
PLH
PHL
7
23
ns
-1.4
ns
t
- t
Driver Propagation-Delay Skew (Note 2)
PDS
| PLH PHL|
DRIVER-OUTPUT ENABLE/DISABLE TIMES (MAX3485E/MAX3491E only)
Driver-Output Enable Time to Low Level
t
R
R
R
R
R
R
= 110Ω, Figure 10
= 110Ω, Figure 9
= 110Ω, Figure 9
= 110Ω, Figure 10
= 110Ω, Figure 10
= 110Ω, Figure 9
42
42
90
90
ns
ns
ns
ns
ns
ns
PZL
L
L
L
L
L
L
Driver-Output Enable Time to High Level
t
t
PZH
PHZ
Driver-Output Disable Time from High Level
Driver-Output Disable Time from Low Level
Driver-Output Enable Time from Shutdown to Low Level
Driver-Output Enable Time from Shutdown to High Level
35
80
t
35
80
PLZ
PSL
PSH
t
650
650
900
900
t
DRIVER SWITCHING CHARACTERISTICS—MAX3486E
(V = +3.3V, T = +25°C.)
CC
A
PARAMETER
SYMBOL
CONDITIONS
MIN
2.5
20
TYP
MAX
UNITS
Mbps
ns
Maximum Data Rate
Driver Differential Output Delay
t
R
R
R
R
R
= 60Ω, Figure 7
= 60Ω, Figure 7
= 27Ω, Figure 8
= 27Ω, Figure 8
= 27Ω, Figure 8
42
28
42
42
-6
70
60
DD
L
L
L
L
L
Driver Differential Output Transition Time
Driver Propagation Delay, Low-to-High Level
Driver Propagation Delay, High-to-Low Level
t
TD
15
ns
t
t
t
20
75
ns
PLH
PHL
20
75
ns
±12
ns
t
- t
Driver Propagation-Delay Skew (Note 2)
PDS
| PLH PHL|
DRIVER-OUTPUT ENABLE/DISABLE TIMES
Driver-Output Enable Time to Low Level
t
R
R
R
R
R
R
= 110Ω, Figure 10
= 110Ω, Figure 9
= 110Ω, Figure 9
= 110Ω, Figure 10
= 110Ω, Figure 10
= 110Ω, Figure 9
52
52
100
100
80
ns
ns
ns
ns
ns
ns
PZL
PZH
PHZ
L
L
L
L
L
L
Driver-Output Enable Time to High Level
t
t
Driver-Output Disable Time from High Level
Driver-Output Disable Time from Low Level
Driver-Output Enable Time from Shutdown to Low Level
Driver-Output Enable Time from Shutdown to High Level
40
t
40
80
PLZ
PSL
PSH
t
700
700
1000
1000
t
_______________________________________________________________________________________
3
3.3V-Pow e re d, ±15kV ESD-Prote c te d, 12Mbps a nd
Sle w -Ra te -Lim ite d True RS -485/RS -422 Tra ns c e ive rs
DRIVER SWITCHING CHARACTERISTICS—MAX3483E/MAX3488E
(V = +3.3V, T = +25°C.)
CC
A
PARAMETER
SYMBOL
CONDITIONS
MIN
250
600
400
700
700
TYP
MAX
UNITS
kbps
ns
Maximum Data Rate
Driver Differential Output Delay
t
R
L
R
L
R
L
R
L
R
L
= 60Ω, Figure 7
= 60Ω, Figure 7
= 27Ω, Figure 8
= 27Ω, Figure 8
= 27Ω, Figure 8
900
740
930
930
±50
1400
1200
1500
1500
DD
Driver Differential Output Transition Time
Driver Propagation Delay, Low-to-High Level
Driver Propagation Delay, High-to-Low Level
t
ns
TD
t
t
t
ns
PLH
PHL
ns
ns
t
- t
Driver Propagation-Delay Skew (Note 2)
PDS
| PLH PHL|
DRIVER-OUTPUT ENABLE/DISABLE TIMES (MAX3483E only)
Driver-Output Enable Time to Low Level
t
R
L
R
L
R
L
R
L
R
L
R
L
= 110Ω, Figure 10
= 110Ω, Figure 9
= 110Ω, Figure 9
= 110Ω, Figure 10
= 110Ω, Figure 10
= 110Ω, Figure 9
900
600
50
1300
800
80
ns
ns
ns
ns
µs
µs
PZL
Driver-Output Enable Time to High Level
t
t
PZH
PHZ
Driver-Output Disable Time from High Level
Driver-Output Disable Time from Low Level
Driver-Output Enable Time from Shutdown to Low Level
Driver-Output Enable Time from Shutdown to High Level
t
50
80
PLZ
PSL
PSH
t
1.9
2.2
2.7
3.0
t
RECEIVER SWITCHING CHARACTERISTICS
(V = +3.3V, T = +25°C.)
CC
A
PARAMETER
SYMBOL
CONDITIONS
MIN
TYP
MAX
UNITS
MAX3483E/MAX3485E/MAX3486E/MAX3491E
only (Note 3)
Time to Shutdown
t
80
190
300
ns
SHDN
V
= 0 to 3.0V, C = 15pF, Figure 11
25
25
25
25
62
75
62
75
6
90
120
90
ID
L
Receiver Propagation Delay,
Low-to-High Level
t
ns
ns
ns
ns
ns
ns
ns
ns
ns
RPLH
RPHL
RPDS
MAX3483E/MAX3488E
= 0 to 3.0V, C = 15pF, Figure 11
V
ID
L
Receiver Propagation Delay,
High-to-Low Level
t
MAX3483E/MAX3488E
= 0 to 3.0V, C = 15pF, Figure 11
120
±10
±20
V
ID
L
t
- t
Receiver
| PLH PHL|
t
Propagation-Delay Skew
MAX3483E/MAX3488E
12
Receiver-Output Enable Time
to Low Level
C = 15pF, Figure 12,
L
MAX3483E/85E/86E/91E only
t
25
25
50
50
PRZL
PRZH
PRHZ
Receiver-Output Enable Time
to High Level
C = 15pF, Figure 12,
L
MAX3483E/85E/86E/91E only
t
t
Receiver-Output Disable
Time from High Level
C = 15pF, Figure 12,
L
MAX3483E/85E/86E/91E only
25
45
Receiver-Output Disable
Time from Low Level
C = 15pF, Figure 12,
L
MAX3483E/85E/86E/91E only
t
25
45
PRLZ
PRSL
PRSH
Receiver-Output Enable Time
from Shutdown to Low Level
C = 15pF, Figure 12,
L
MAX3483E/85E/86E/91E only
t
720
720
1400
1400
Receiver-Output Enable Time
from Shutdown to High Level
C = 15pF, Figure 12,
L
MAX3483E/85E/86E/91E only
t
Note 1: ∆V and ∆V are the changes in V and V , respectively, when the DI input changes state.
OD
OC
OD
OC
Note 2: Measured on |t
(Y) - t
(Y)| and |t
(Z) - t
(Z)|.
PLH
PHL
PLH
PHL
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
devices are guaranteed not to enter shutdown. If the inputs are in this state for at least 300ns, the devices are guaranteed
to have entered shutdown. See Low-Power Shutdown Mode section.
5680/MAX3491E
4
_______________________________________________________________________________________
3.3V-Pow e re d, ±15kV ESD-Prote c te d, 12Mbps a nd
Sle w -Ra te -Lim ite d True RS -485/RS -422 Tra ns c e ive rs
5680/MAX3491E
Typ ic a l Op e ra t in g Ch a ra c t e ris t ic s
(V = +3.3V, T = +25°C, unless otherwise noted.)
CC
A
OUTPUT CURRENT vs.
RECEIVER OUTPUT LOW VOLTAGE
OUTPUT CURRENT vs.
RECEIVER OUTPUT HIGH VOLTAGE
RECEIVER OUTPUT HIGH VOLTAGE
vs. TEMPERATURE
25
-20
-18
-16
-14
-12
-10
-8
3.30
3.25
I
RO
= 1.5mA
20
15
10
5
3.20
3.15
3.10
3.05
3.00
-6
-4
-2
0
0
0
0.5 1.0 1.5 2.0 2.5 3.0 3.5
OUTPUT LOW VOLTAGE (V)
0
0.5 1.0 1.5 2.0 2.5 3.0 3.5
OUTPUT HIGH VOLTAGE (V)
-40 -20
0
20
40
60
80 100
TEMPERATURE (°C)
RECEIVER OUTPUT LOW VOLTAGE
vs. TEMPERATURE
DRIVER OUTPUT CURRENT vs.
DIFFERENTIAL OUTPUT VOLTAGE
DRIVER DIFFERENTIAL OUTPUT
VOLTAGE vs. TEMPERATURE
100
90
80
70
60
50
40
30
0.8
0.7
0.6
0.5
2.6
2.5
I
RO
= 2.5mA
R = 54Ω
2.4
2.3
2.2
2.1
0.4
0.3
0.2
0.1
0
2.0
1.9
1.8
1.7
1.6
20
10
0
-40 -20
0
20
40
60
80 100
0
0.5 1.0 1.5 2.0 2.5 3.0 3.5
DIFFERENTIAL OUTPUT VOLTAGE (V)
-40 -20
0
20
40
60
80 100
TEMPERATURE (°C)
TEMPERATURE (°C)
OUTPUT CURRENT vs.
DRIVER OUTPUT LOW VOLTAGE
OUTPUT CURRENT vs.
DRIVER OUTPUT HIGH VOLTAGE
175
-100
-80
150
125
100
75
-60
-40
-20
0
50
25
0
0
2
4
6
8
10
12
0
1
2
3
4
5
-7 -6 -5 -4 -3 -2 -1
OUTPUT LOW VOLTAGE (V)
OUTPUT HIGH VOLTAGE (V)
_______________________________________________________________________________________
5
3.3V-Pow e re d, ±15kV ESD-Prote c te d, 12Mbps a nd
Sle w -Ra te -Lim ite d True RS -485/RS -422 Tra ns c e ive rs
Typ ic a l Op e ra t in g Ch a ra c t e ris t ic s (c o n t in u e d )
(V = +3.3V, T = +25°C, unless otherwise noted.)
CC
A
SHUTDOWN CURRENT
vs. TEMPERATURE
SUPPLY CURRENT
vs. TEMPERATURE
100
90
1.2
X = DON’T CARE
80
70
60
1.1
1.0
0.9
DE = V , RE = X
CC
50
DE = 0, RE = 0
40
30
20
10
0
0.8
0.7
-40 -20
0
20
40
60
80 100
-40 -20
0
20
40
60
80 100
TEMPERATURE (°C)
TEMPERATURE (°C)
P in De s c rip t io n
PIN
MAX3483E
MAX3485E
MAX3486E
NAME
FUNCTION
MAX3488E
MAX3490E
MAX3491E
Receiver Output. If A > B by 200mV, RO will be high; if A < B by 200mV,
RO will be low.
1
2
2
2
3
RO
Receiver Output Enable. RO is enabled when RE is low; RO is high imped-
ance when RE is high. If RE is high and DE is low, the device will enter a
low-power shutdown mode.
—
RE
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.
3
4
—
3
4
5
DE
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
5
6, 7
9
GND
Y
Ground
—
—
6
Noninverting Driver Output
6
10
Z
Inverting Driver Output
—
8
—
A
Noninverting Receiver Input and Noninverting Driver Output
Noninverting Receiver Input
—
7
12
A
—
7
—
B
Inverting Receiver Input and Inverting Driver Output
Inverting Receiver Input
—
8
11
B
1
13, 14
1, 8
V
CC
Positive Supply: 3.0V ≤ V ≤ 3.6V. Do not operate device with V > 3.6V.
CC CC
—
—
N.C.
No Connection. Not internally connected.
5680/MAX3491E
6
_______________________________________________________________________________________
3.3V-Pow e re d, ±15kV ESD-Prote c te d, 12Mbps a nd
Sle w -Ra te -Lim ite d True RS -485/RS -422 Tra ns c e ive rs
5680/MAX3491E
TOP VIEW
DE
MAX3483E
MAX3485E
MAX3486E
R
R
1
2
3
4
RO
RE
DE
DI
1
2
3
4
RO
RE
DE
DI
8
8
7
6
5
V
CC
B
Rt
V
D
DI
CC
B
A
7
B
Rt
6
A
A
RO
R
D
D
5
GND
GND
RE
NOTE: PIN LABELS Y AND Z ON TIMING, TEST, AND WAVEFORM DIAGRAMS REFER TO PINS A AND B WHEN DE IS HIGH.
SO/DIP
Figure 1. MAX3483E/MAX3485E/MAX3486E Pin Configuration and Typical Operating Circuit
V
CC
V
CC
TOP VIEW
1
MAX3488E
MAX3490E
Y
5
3
2
Rt
DI
RO
DI
D
R
V
1
2
3
4
R
8
7
6
5
A
B
Z
CC
6 Z
RO
DI
8
7
A
Rt
RO
R
D
GND
Y
D
B
SO/DIP
4
GND
GND
Figure 2. MAX3488E/MAX3490E Pin Configuration and Typical Operating Circuit
DE
V
V
CC
RE
TOP VIEW
CC
MAX3491E
4
13, 14
N.C.
1
2
3
4
5
6
7
14
13
12
11
10
9
V
CC
9
Y
R
5
V
CC
Rt
RO
RE
RO
DI
DI
D
R
10
A
Z
DE
B
12
11
A
DI
Z
2
Rt
RO
R
D
D
GND
GND
Y
B
8
N.C.
1, 8
N.C.
3
6, 7
SO/DIP
RE GND
GND DE
Figure 3. MAX3491E Pin Configuration and Typical Operating Circuit
_______________________________________________________________________________________
7
3.3V-Pow e re d, ±15kV ESD-Prote c te d, 12Mbps a nd
Sle w -Ra te -Lim ite d True RS -485/RS -422 Tra ns c e ive rs
375Ω
R
L
2
V
CM
=
-7V to +12V
V
OD
R
L
D
V
OD
D
R
L
V
OC
V
CC
2
V
CC
375Ω
Figure 4. Driver V and V
Figure 5. Driver V with Varying Common-Mode Voltage
OD
OC
OD
V
ID
R
0
V
OL
V
OH
I
OL
I
OH
(+)
(-)
Figure 6. Receiver V and V
OH
OL
3V
IN
1.5V
1.5V
C
L
0
OUT
D
R =
60Ω
L
t
DD
t
DD
GENERATOR
(NOTE 4)
50Ω
≈ 2.0V
90%
90%
V
CC
50%
10%
50%
10%
OUT
C
L
≈ -2.0V
C = 15pF (NOTE 5)
L
t
TD
t
TD
Figure 7. Driver Differential Output Delay and Transition Times
5680/MAX3491E
8
_______________________________________________________________________________________
3.3V-Pow e re d, ±15kV ESD-Prote c te d, 12Mbps a nd
Sle w -Ra te -Lim ite d True RS -485/RS -422 Tra ns c e ive rs
5680/MAX3491E
3V
V
OM
IN
1.5V
1.5V
R = 27Ω
L
0V
S1
t
t
PHL
PLH
OUT
D
V
OH
GENERATOR
(NOTE 4)
Y
OUT
50Ω
C = 15pF
L
(NOTE 5)
V
OM
V
OM
V
CC
V
OL
t
t
PLH
PHL
V
+ V
OH OL
≈ 1.5V
2
V
OM
=
V
OH
Z
OUT
V
OM
V
OM
V
OL
Figure 8. Driver Propagation Times
3V
S1
OUT
0 OR 3V
D
IN
1.5V
1.5V
0
R = 110Ω
L
C = 50pF
L
(NOTE 5)
t
t
PHZ
PZH
GENERATOR
(NOTE 4)
V
OH
50Ω
0.25V
OUT
V
OM
V
+ V
OH OL
≈ 1.5V
2
V
OM
=
0
Figure 9. Driver Enable and Disable Times (t
, t
, t
)
PZH PSH PHZ
V
CC
3V
0
R = 110Ω
L
IN
1.5V
1.5V
S1
0 OR 3V
OUT
D
t
t
PLZ
PSL
C = 50pF
L
(NOTE 5)
V
CC
GENERATOR
(NOTE 4)
OUT
V
OM
50Ω
0.25V
V
OL
Figure 10. Driver Enable and Disable Times (t , t , t
)
PZL PSL PLZ
_______________________________________________________________________________________
9
3.3V-Pow e re d, ±15kV ESD-Prote c te d, 12Mbps a nd
Sle w -Ra te -Lim ite d True RS -485/RS -422 Tra ns c e ive rs
3.0V
OUT
V
ID
R
IN
1.5V
1.5V
GENERATOR
(NOTE 4)
50Ω
C = 15pF
L
0
(NOTE 5)
t
t
RPHL
RPLH
V
CC
1.5V
0
V
OM
V
OM
OUT
V
2
CC
V
OM
=
0
Figure 11. Receiver Propagation Delay
S1
S3
1.5V
1k
V
CC
-1.5V
V
ID
R
S2
C
L
(NOTE 5)
GENERATOR
(NOTE 4)
50Ω
3V
0
3V
S1 OPEN
S2 CLOSED
S3 = 1.5V
S1 CLOSED
S2 OPEN
S3 = -1.5V
IN
IN
1.5V
1.5V
0
t
t
PRZL
PRZH
t
t
PRSH
PRSL
V
OH
V
CC
OUT
OUT
1.5V
1.5V
0
V
OL
3V
0
3V
0
S1 OPEN
S2 CLOSED
S3 = 1.5V
S1 CLOSED
S2 OPEN
S3 = -1.5V
IN
1.5V
IN
1.5V
t
PRHZ
t
PRLZ
V
OH
V
CC
OUT
0.25V
OUT
0.25V
0
V
OL
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, t ≤ 6.0ns, Z = 50Ω.
r
O
Note 5: C includes probe and stray capacitance.
L
5680/MAX3491E
10 ______________________________________________________________________________________
3.3V-Pow e re d, ±15kV ESD-Prote c te d, 12Mbps a nd
Sle w -Ra te -Lim ite d True RS -485/RS -422 Tra ns c e ive rs
5680/MAX3491E
_____________________Fu n c t io n Ta b le s
___________Ap p lic a t io n s In fo rm a t io n
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 trans-
ceivers, 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.
De vic e s w it h Re c e ive r/Drive r En a b le
(MAX3483E/MAX3485E/MAX3486E/MAX3491E)
Table 1. Transmitting
INPUTS
OUTPUTS
MODE
DE
1
DI
1
B*
A*
1
RE
X
X
0
0
Normal
Normal
1
0
1
0
0
X
X
High-Z
High-Z
High-Z
High-Z
Normal
1
0
Shutdown
Re d u c e d EMI a n d Re fle c t io n s
(MAX3 4 8 3 E/MAX3 4 8 6 E/MAX3 4 8 8 E)
* B and A outputs are Z and Y, respectively, for full-duplex part
(MAX3491E).
The MAX3483E/MAX3488E are slew-rate limited, mini-
mizing EMI and reducing reflections caused by improp-
e rly te rmina te d c a b le s . Fig ure 13 s hows the d rive r
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
s a me informa tion, b ut for the s le w-ra te -limite d
MAX3483E/MAX3488E transmitting the same signal. The
high-frequency harmonics have much lower amplitudes,
and the potential for EMI is significantly reduced.
X = Don’t care; High-Z = High impedance
Table 2. Receiving
INPUTS
DE
OUTPUTS
MODE
A, B
≥ +0.2V
≤ -0.2V
Inputs Open
X
RO
RE
0
0*
0*
0*
0
1
Normal
Normal
0
0
1
0
Normal
1
High-Z
Shutdown
* DE is a “don’t care” (x) for the full-duplex part (MAX3491E).
X = Don’t care; High-Z = High impedance
Lo w -P o w e r S h u t d o w n Mo d e
(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.
De vic e s w it h o u t Re c e ive r/Drive r En a b le
(MAX3 4 8 8 E/MAX3 4 9 0 E)
Table 3. Transmitting Table 4. Receiving
INPUT
OUTPUTS
INPUTS
OUTPUT
For the s e d e vic e s , the tPSH a nd tPSL e na b le time s
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.
DI
1
Z
0
1
Y
1
A, B
RO
1
≥ +0.2V
≤ -0.2V
0
0
0
Inputs Open
1
10dB/div
10dB/div
0
500kHz/div
5MHz
0
500kHz/div
5MHz
Figure 13. Driver Output Waveform and FFT Plot of MAX3485E/
MAX3490E/MAX3491E Transmitting a 125kHz Signal
Figure 14. Driver Output Waveform and FFT Plot of
MAX3483E/ MAX3488E Transmitting a 125kHz Signal
______________________________________________________________________________________ 11
3.3V-Pow e re d, ±15kV ESD-Prote c te d, 12Mbps a nd
Sle w -Ra te -Lim ite d True RS -485/RS -422 Tra ns c e ive rs
B
1V/div
DI
2V/div
A
1V/div
Z
1V/div
RO
Y
2V/div
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
DI
5V/div
5V/div
V - V
V - V
Y
Z
Y
Z
2V/div
2V/div
RO
RO
5V/div
5V/div
2µs/div
2µs/div
Figure 19. MAX3483E/MAX3488E System Differential Voltage at
125kHz Driving 4000 Feet of Cable
Figure 20. MAX3485E/MAX3490E/MAX3491E System Differential
Voltage at 125kHz Driving 4000 Feet of Cable
5680/MAX3491E
12 ______________________________________________________________________________________
3.3V-Pow e re d, ±15kV ESD-Prote c te d, 12Mbps a nd
Sle w -Ra te -Lim ite d True RS -485/RS -422 Tra ns c e ive rs
5680/MAX3491E
Drive r-Ou t p u t P ro t e c t io n
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 shut-
down circuit forces the driver outputs into a high-imped-
ance state if the die temperature rises excessively.
±1 5 k V ES D P ro t e c t io n
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-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, Maxim’s E versions
keep working without latchup or damage.
P ro p a g a t io n De la y
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).
ESD p rote c tion c a n b e te s te d in va rious wa ys ; the
transmitter outputs and receiver inputs of this product
family are characterized for protection to the following
limits:
The receiver skew time, t
- tPRHL|, is under 10ns
| PRLH
1) ±15kV using the Human Body Model
(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.
2) ±8kV using the Contact-Discharge method specified
in IEC 1000-4-2
3) ±15kV using IEC 1000-4-2’s Air-Gap method.
Lin e Le n g t h vs . Da t a Ra t e
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.
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.
Figures 19 and 20 show the system differential voltage
for parts driving 4000 feet of 26AWG twisted-pair wire
at 125kHz into 120Ω loads.
Human Body Model
Figure 22a shows the Human Body Model and Figure
22b shows the current waveform it generates when dis-
charged into a low impedance. This model consists of
a 100pF capacitor charged to the ESD voltage of inter-
e s t, whic h is the n d is c ha rg e d into the te s t d e vic e
through a 1.5kΩ resistor.
For faster data rate transmission, please consult the fac-
tory.
MAX3488E
MAX3490E
MAX3491E
IEC 1000-4-2
The IEC 1000-4-2 standard covers ESD testing and
performance of finished equipment; it does not specifi-
cally 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.
A
120Ω
RO
RE
DE
R
DATA IN
B
Z
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 with-
stand voltage measured to IEC 1000-4-2 is generally
lowe r tha n tha t me a s ure d us ing the Huma n Bod y
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.
DI
120Ω
DATA OUT
D
Y
NOTE: RE AND DE ON MAX3491E ONLY.
Figure 21. Line Repeater for MAX3488E/MAX3490E/MAX3491E
______________________________________________________________________________________ 13
3.3V-Pow e re d, ±15kV ESD-Prote c te d, 12Mbps a nd
Sle w -Ra te -Lim ite d True RS -485/RS -422 Tra ns c e ive rs
R
C
R
D
1M
1500Ω
I 100%
P
90%
PEAK-TO-PEAK RINGING
(NOT DRAWN TO SCALE)
I
r
DISCHARGE
RESISTANCE
CHARGE-CURRENT
LIMIT RESISTOR
AMPERES
HIGH-
VOLTAGE
DC
DEVICE
UNDER
TEST
36.8%
C
100pF
STORAGE
CAPACITOR
s
10%
0
SOURCE
TIME
0
t
RL
t
DL
CURRENT WAVEFORM
Figure 22b. Human Body Current Waveform
Figure 22a. Human Body ESD Test Model
R
R
D
330Ω
C
I
50M to 100M
100%
90%
DISCHARGE
RESISTANCE
CHARGE-CURRENT
LIMIT RESISTOR
HIGH-
VOLTAGE
DC
DEVICE
UNDER
TEST
C
s
150pF
STORAGE
CAPACITOR
SOURCE
10%
Figure 23a. IEC 1000-4-2 ESD Test Model
t
t = 0.7ns to 1ns
r
30ns
60ns
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.
Typ ic a l Ap p lic a t io n s
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 net-
work applications circuits. These parts can also be
used as line repeaters, with cable lengths longer than
4000 feet, as shown in Figure 21.
Machine Model
The Ma c hine Mod e l for ESD te s ts a ll p ins us ing a
200pF storage capacitor and zero discharge resis -
tance. 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.
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.
5680/MAX3491E
14 ______________________________________________________________________________________
3.3V-Pow e re d, ±15kV ESD-Prote c te d, 12Mbps a nd
Sle w -Ra te -Lim ite d True RS -485/RS -422 Tra ns c e ive rs
5680/MAX3491E
120Ω
120Ω
DE
DI
B
A
B
A
DI
D
D
DE
B
A
B
A
RO
RE
RO
RE
R
R
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
Y
120Ω
120Ω
120Ω
RO
RE
R
DI
D
B
Z
Z
B
DE
DE
RE
RO
120Ω
DI
R
D
Y
A
Y
Z
B
A
Y
Z
B
A
R
R
D
D
DI
MAX3488E
MAX3490E
MAX3491E
DE RE RO
DI
DE RE RO
NOTE: RE AND DE ON MAX3491E ONLY.
Figure 25. MAX3488E/MAX3490E/MAX3491E Full-Duplex RS-485 Network
______________________________________________________________________________________ 15
3.3V-Pow e re d, ±15kV ESD-Prote c te d, 12Mbps a nd
Sle w -Ra te -Lim ite d True RS -485/RS -422 Tra ns c e ive rs
Ord e rin g In fo rm a t io n (c o n t in u e d )
Ch ip In fo rm a t io n
PART
TEMP. RANGE
0°C to +70°C
0°C to +70°C
-40°C to +85°C
-40°C to +85°C
0°C to +70°C
0°C to +70°C
-40°C to +85°C
-40°C to +85°C
0°C to +70°C
0°C to +70°C
-40°C to +85°C
-40°C to +85°C
0°C to +70°C
0°C to +70°C
-40°C to +85°C
-40°C to +85°C
PIN-PACKAGE
8 SO
TRANSISTOR COUNT: 761
MAX3486ECSA
MAX3486ECPA
MAX3486EESA
MAX3486EEPA
MAX3488ECSA
MAX3488ECPA
MAX3488EESA
MAX3488EEPA
MAX3490ECSA
MAX3490ECPA
MAX3490EESA
MAX3490EEPA
MAX3491ECSD
MAX3491ECPD
MAX3491EESD
MAX3491EEPD
8 Plastic DIP
8 SO
8 Plastic DIP
8 SO
8 Plastic DIP
8 SO
8 Plastic DIP
8 SO
8 Plastic DIP
8 SO
8 Plastic DIP
14 SO
14 Plastic DIP
14 SO
14 Plastic DIP
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.
5680/MAX3491E
16 ____________________Ma x im In t e g ra t e d P ro d u c t s , 1 2 0 S a n Ga b rie l Drive , S u n n yva le , CA 9 4 0 8 6 4 0 8 -7 3 7 -7 6 0 0
© 1999 Maxim Integrated Products
Printed USA
is a registered trademark of Maxim Integrated Products.
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