General Description
The MAX13485E/MAX13486E +5V, half-duplex, ±15kV
ESD-protected RS-485 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 logichigh if all transmitters on a terminated bus are disabled
(high impedance). The MAX13485E/MAX13486E include
a hot-swap capability to eliminate false transitions on the
bus during power-up or live-insertion.
The MAX13485E features reduced slew-rate drivers
that minimize EMI and reduce reflections caused by
improperly terminated cables, allowing error-free transmission up to 500kbps. The MAX13486E driver slew
rate is not limited, allowing transmit speeds up to
16Mbps.
The MAX13485E/MAX13486E feature a 1/4-unit load
receiver input impedance, allowing up to 128 transceivers
on the bus. These devices are intended for half-duplex
communications. All driver outputs are protected to ±15kV
ESD using the Human Body Model. The MAX13485E/
MAX13486E are available in 8-pin SO and space-saving
8-pin µDFN packages. The devices operate over the
extended -40°C to +85°C temperature range.
Applications
Utility Meters
Industrial Controls
Industrial Motor Drives
Automated HVAC Systems
Features
♦ +5V Operation
♦ True Fail-Safe Receiver While Maintaining
EIA/TIA-485 Compatibility
♦ Hot-Swappable for Telecom Applications
♦ Enhanced Slew-Rate Limiting Facilitates Error-
Free Data Transmission (MAX13485E)
♦ High-Speed Version (MAX13488E) Allows for
Transmission Speeds Up to 16Mbps
♦ Extended ESD Protection for RS-485/RS-422 I/O
Pins ±15kV Using Human Body Model
♦ 1/4 Unit Load, Allowing Up to 128 Transceivers on
the Bus
♦ Available in Space-Saving 8-Pin µDFN or Industry
Standard 8-Pin SO Packages
MAX13485E/MAX13486E
Half-Duplex RS-485/RS-422 Transceivers in µDFN
________________________________________________________________ Maxim Integrated Products 1
19-0742; Rev 0; 1/07
For pricing, delivery, and ordering information, please contact Maxim/Dallas Direct! at
1-888-629-4642, or visit Maxim’s website at www.maxim-ic.com.
Ordering Information/
Selector Guide
SLEW-RATE
LIMITED
PKG
CODE
MAX13485EESA+ 8 SO Yes S8-2
MAX13486EESA+ 8 SO No S8-2
+Denotes a lead-free package.
Note: All devices are specified over the -40°C to +85°C operating
temperature range.
Rt
RE
RO
B
A
A
B
Rt
R
D
RO
DI
8
7
6
5
1
2
3
4
RE
DE
R
DI
D
DE
+
123
87465
V
CC
A GNDB
RO DIDERE
MAX13485E
MAX13486E
DFN
+
A
GNDDI
1
2
87V
CC
BRE
DE
RO
SO
SO
3
4
6
5
R
D
+
TOP VIEW
GND
V
CC
0.1µF
MAX13485E
MAX13486E
PACKAGE
MAX13485E/MAX13486E
Half-Duplex RS-485/RS-422 Transceivers in µDFN
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.
(All voltages referenced to GND.)
V
CC
........................................................................................+6V
DE,
RE, DI.................................................................-0.3V to +6V
A, B ..............................................................................-8V to 13V
Short-Circuit Duration (RO, A, B) to GND ..................Continuous
Continuous Power Dissipation (T
A
= +70°C)
8-Pin SO (derate 5.9mW/°C above +70°C)..................471mW
8-Pin µDFN (derate 4.8mW/°C above +70°C) ..........380.6mW
Operating Temperature Range ...........................-40°C to +85°C
Junction Temperature......................................................+150°C
Storage Temperature Range .............................-65°C to +150°C
Lead Temperature (soldering, 10s) .................................+300°C
ELECTRICAL CHARACTERISTICS
(VCC= +5V ±5%, TA= T
MIN
to T
MAX
, unless otherwise noted. Typical values are at VCC= +5V and TA= +25°C.) (Notes 1, 2)
DRIVER
R
DIFF
= 100Ω, Figure 1 2.0
R
DIFF
= 54Ω, Figure 1 1.5Differential Driver Output V
OD
No load
V
Change in Magnitude of
Differential Output Voltage
∆V
OD
R
DIFF
= 100Ω or 54Ω, Figure 1 (Note 3) 0.2 V
Driver Common-Mode Output
Voltage
V
OC
R
DIFF
= 100Ω or 54Ω, Figure 1
V
CC
/ 2
3V
Change in Magnitude of
Common-Mode Voltage
∆V
OC
R
DIFF
= 100Ω or 54Ω, Figure 1 (Note 3) 0.2 V
Input-High Voltage V
IH
DI, DE, RE 2.0 V
Input-Low Voltage V
IL
DI, DE, RE 0.8 V
Input Current I
IN
DI, DE, RE ±1 µA
0V
Driver Short-Circuit Output
Current (Note 4)
I
OSD
-7V
+12V 20
Driver Short-Circuit Foldback
Output Current Note 3)
I
OSDF
-7V
0V -20
mA
RECEIVER
VIN = +12V
Input Current (A and B) I
A, B
DE = GND, VCC = GND
or +5V
V
IN
= -7V
µA
Receiver-Differential-Threshold
Voltage
V
TH
-7V
-50 mV
Receiver Input Hysteresis ∆V
TH
VA + VB = 0V 25 mV
Output-High Voltage V
OH
IO = -1.6mA, VA - VB > V
TH
V
CC
-
1.5
V
V
CC
V
CC
+50 +250
-250
-200
-200
250
MAX13485E/MAX13486E
Half-Duplex RS-485/RS-422 Transceivers in µDFN
_______________________________________________________________________________________ 3
ELECTRICAL CHARACTERISTICS (continued)
(VCC= +5V ±5%, TA= T
MIN
to T
MAX
, unless otherwise noted. Typical values are at VCC= +5V and TA= +25°C.) (Notes 1, 2)
Output-Low Voltage V
OL
IO = 1mA, VA - VB < -V
TH
0.4 V
Tri-State Output Current at
Receiver
I
OZR
0V
V
CC
±1 µA
Receiver Input Resistance R
IN
-7V
+12V 48 kΩ
Receiver-Output Short-Circuit
Current
I
OSR
0V
mA
POWER SUPPLY
Supply Voltage V
CC
V
Supply Current I
CC
DE = 1, RE = 0, no load 4.5 mA
Shutdown Supply Current I
SHDN
DE = 0, RE = 1 10 µA
ESD PROTECTION
Air Gap Discharge IEC61000-4-2
(MAX13485E)
ESD Protection (A, B)
Human Body Model
kV
ESD Protection (All Other Pins) Human Body Model ±2 kV
SWITCHING CHARACTERISTICS—MAX13485E
(VCC= +5V ±5%, TA= T
MIN
to T
MAX
, unless otherwise noted. Typical values are at VCC= +5V and TA= +25°C.) (Note 1)
Driver Propagation Delay
t
DPHL
R
DIFF
= 54Ω, CL = 50pF, Figures 2 and 3
Driver-Differential Output Rise or
Fall Time
t
LH
R
DIFF
= 54Ω, CL = 50pF, Figures 2 and 3
ns
Driver-Differential Output Skew
|t
DPLH
- t
DPHL
|
R
DIFF
= 54Ω, CL = 50pF, Figures 2 and 3
Driver Enable to Output High t
DZH
Figures 4 and 5
ns
Driver Enable to Output Low t
DZL
Figures 4 and 5
ns
Driver Disable Time from High t
DHZ
Figures 4 and 5
ns
Driver Disable Time from Low t
DLZ
Figures 4 and 5
ns
Driver Enable from Shutdown to
Output High
ns
Driver Enable from Shutdown to
Output Low
ns
Time to Shutdown t
SHDN
50 340
ns
RECEIVER
t
RPLH
80
Receiver Propagation Delay
t
RPHL
CL = 15pF, Figures 6 and 7
80
ns
Receiver Output Skew t
RSKEWCL
= 15pF, Figure 7 13 ns
Maximum Data Rate
±95
4.75 5.25
±15
±15
200 1000
200 1000
250 900
250 900
t
DSKEW
t
DZH(SHDN
t
DZL(SHDN
500
500
140
2500
2500
100
100
5500
5500
700
MAX13485E/MAX13486E
Half-Duplex RS-485/RS-422 Transceivers in µDFN
4 _______________________________________________________________________________________
SWITCHING CHARACTERISTICS—MAX13485E (continued)
(VCC= +5V ±5%, TA= T
MIN
to T
MAX
, unless otherwise noted. Typical values are at VCC= +5V and TA= +25°C.) (Note 1)
Receiver Enable to Output High t
RZH
Figure 8 50 ns
Receiver Enable to Output Low t
RZL
Figure 8 50 ns
Receiver Disable Time from High
Receiver Disable Time from Low
t
RLZ
Figure 8 50 ns
Receiver Enable from Shutdown
to Output High
ns
Receiver Enable from Shutdown
to Output Low
ns
Time to Shutdown t
SHDN
50 340
SWITCHING CHARACTERISTICS—MAX13486E
(VCC= +5V ±5%, TA= T
MIN
to T
MAX
, unless otherwise noted. Typical values are at VCC= +5V and TA= +25°C.) (Note 1)
DRIVER
t
DPLH
50
Driver Propagation Delay
t
DPHL
R
DIFF
= 54Ω, CL = 50pF, Figures 2 and 3
50
ns
t
HL
15
Driver Differential Output Rise or
Fall Time
t
LH
R
DIFF
= 54Ω, CL = 50pF, Figures 2 and 3
15
ns
Differential Driver Output Skew
|t
DPLH
- t
DPHL
|
R
DIFF
= 54Ω, CL = 50pF, Figures 2 and 3 8 ns
Maximum Data Rate 16
Driver Enable to Output High t
DZH
Figures 4 and 5 50 ns
Driver Enable to Output Low t
DZL
Figures 4 and 5 50 ns
Driver Disable Time from High t
DHZ
Figures 4 and 5 50 ns
Driver Disable Time from Low t
DLZ
Figures 4 and 5 50 ns
Driver Enable from Shutdown to
Output High
ns
Driver Enable from Shutdown to
Output Low
ns
Time to Shutdown t
SHDN
50 340
ns
RECEIVER
t
RPLH
80
Receiver Propagation Delay
t
RPHL
CL = 15pF, Figures 6 and 7
80
ns
Receiver Output Skew t
RSKEWCL
= 15pF, Figure 7 13 ns
Maximum Data Rate 16
t
RZH(SHDN
t
RZL(SHDN
SYMBOL
t
DSKEW
t
DZH(SHDN
t
DZL(SHDN
2200
2200
700
MIN TYP MAX
2200
2200
700
MAX13485E/MAX13486E
Half-Duplex RS-485/RS-422 Transceivers in µDFN
_______________________________________________________________________________________ 5
SWITCHING CHARACTERISTICS—MAX13486E (continued)
(VCC= +5V ±5%, TA= T
MIN
to T
MAX
, unless otherwise noted. Typical values are at VCC= +5V and TA= +25°C.) (Note 1)
Receiver Enable to Output High t
RZH
Figure 8 50 ns
Receiver Enable to Output Low t
RZL
Figure 8 50 ns
Receiver Disable Time from High
Receiver Disable Time from Low
t
RLZ
Figure 8 50 ns
Receiver Enable from Shutdown
to Output High
ns
Receiver Enable from Shutdown
to Output Low
ns
Time to Shutdown t
SHDN
50 340
Note 1: µDFN devices production tested at +25°C. Overtemperature limits are generated by design.
Note 2: All currents into the device are positive. All currents out of the device are negative. All voltages referred to device ground,
unless otherwise noted.
Note 3: ∆V
OD
and ∆VOCare the changes in VODand VOCwhen the DI input changes states.
Note 4: The short-circuit output current applied 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.
Typical Operating Characteristics
(VCC= +5V, TA = +25°C, unless otherwise noted.)
3.0
3.2
3.6
3.4
3.8
4.0
-40 10-15 35 60 85
SUPPLY CURRENT vs. TEMPERATURE
MAX13485-86E toc01
TEMPERATURE (°C)
SUPPLY CURRENT (mA)
NO LOAD
0
7
21
14
28
35
021345
OUTPUT CURRENT vs. RECEIVER
OUTPUT HIGH VOLTAGE
MAX13485-86E toc02
OUTPUT HIGH VOLTAGE (V)
OUTPUT CURRENT (mA)
0
20
10
40
30
50
60
021345
OUTPUT CURRENT vs. RECEIVER
OUTPUT LOW VOLTAGE
MAX13485-86E toc03
OUTPUT LOW VOLTAGE (V)
OUTPUT CURRENT (mA)
t
RZH(SHDN
t
RZL(SHDN
2200
2200
700