MAX14853/MAX14855 isolated RS-485/RS-422 transceivers

EVALUATION KIT AVAILABLE
2.75kVRMS Isolated 500kbps/25Mbps Full-Duplex
RS-485/RS-422 Transceivers with ±35kV ESD
Protection and Integrated Transformer Driver
General Description
The MAX14853/MAX14855 isolated RS-485/RS-422
transceivers provide 2750VRMS (60s) of galvanic isolation between the cable-side (RS-485/RS-422 driver/
receiver-side) and the UART-side of the device. Isolation
improves communication by breaking ground loops and
reduces noise when there are large differences in ground
potential between ports. These devices allow for robust
communication up to 500kbps (MAX14853) or 25Mbps
(MAX14855).
The MAX14853/MAX14855 include an integrated 450kHz
transformer driver for power transfer to the cable-side of
the transceiver using an external transformer. An integrated
LDO provides a simple and space-efficient architecture
for providing power to the cable-side of the IC.
The MAX14853/MAX14855 include one drive channel
and one receive channel. The receiver is ¼-unit load,
allowing up to 128 transceivers on a common bus.
Integrated true fail-safe circuitry ensures a logic-high on
the receiver output when inputs are shorted or open.
Undervoltage lockout disables the driver when cable-side
or UART-side power supplies are below functional levels.
The driver outputs and receiver inputs are protected
from ±35kV electrostatic discharge (ESD) to GNDB on
the cable-side, as specified by the Human Body Model
(HBM).
The MAX14853/MAX14855 are available in a wide body
16-pin SOIC package and operate over the -40°C to
+105°C temperature range.
Benefits and Features
●● Higher Integration Simplifies Designs
• Integrated LDO for Powering Cable Side
• Integrated Transformer Driver for Power Transfer to
Cable Side
●● High-Performance Transceiver Enables Flexible
Designs
• Compliant with RS-485 EIA/TIA-485 Standard
• 500kbps (MAX14853)/25Mbps (MAX14855)
Maximum Data Rate
• Up to 128 Devices on the Bus
• Slew-Rate Limited Outputs (MAX14853)
• Integrated Receiver Deglitch Filter Increases Noise
Immunity (MAX14853)
●● Integrated Protection Ensures for Robust
Communication
• ±35kV ESD (HBM) on Driver Outputs/Receiver
Inputs
• 2.75kVRMS Withstand Isolation Voltage for 60s (VISO)
• 630VPEAK Maximum Repetitive Peak Isolation
Voltage (VIORM)
• 445VRMS Maximum Working Isolation Voltage
(VIOWM)
• > 30 Years Lifetime at Rated Working Voltage
• Withstands ±10kV Surge per IEC 61000-4-5
• Thermal Shutdown
Functional Diagram
Applications
●●
●●
●●
●●
Industrial Automation Equipment
Programmable Logic Controllers
HVAC
Power Meters
Safety Regulatory Approvals (Pending)
●● UL According to UL1577
●● cUL According to CSA Bulletin 5A
●● VDE 0884-10
Ordering Information appears at end of data sheet.
19-7546; Rev 3; 1/16
VDDA
TD1 TD2
XFMR
DRIVER
VLDO
LDO
MAX14853
MAX14855
VDDB
RE
A
RXD
RS-485
TRANSCEIVER
MAX14853/MAX14855
TXD
DE
B
Z
Y
GNDA
GNDB
MAX14853/MAX14855
2.75kVRMS Isolated 500kbps/25Mbps Full-Duplex
RS-485/RS-422 Transceivers with ±35kV ESD
Protection and Integrated Transformer Driver
Absolute Maximum Ratings
VDDA to GNDA ........................................................-0.3V to +6V
VDDB to GNDB........................................................-0.3V to +6V
VLDO to GNDB......................................................-0.3V to +16V
TD1, TD2 to GNDA ...............................................-0.3V to +12V
TXD, DE, RE, RXD to GNDA ..................................-0.3V to +6V
A, B, Y, Z to GNDB....................................................-8V to +13V
TD1, TD2 Continuous Current..............................................1.4A
Short-Circuit Duration (RXD to GNDA, A, B, Y, Z,
VDDB to GNDB)....................................................Continuous
Continuous Power Dissipation (TA = +70°C)
16-pin Wide SOIC
(derate 14.1mW/°C above +70°C).......................... 1126.8mW
Operating Temperature Range.......................... -40°C to +105°C
Junction Temperature.......................................................+150°C
Storage Temperature Range............................. -65°C to +150°C
Lead Temperature (soldering, 10s).................................. +300°C
Soldering Temperature (reflow)........................................+260°C
Stresses beyond those listed under “Absolute Maximum Ratings” may cause permanent damage to the device. These are stress ratings only, and functional operation of the device at these
or any other conditions beyond those indicated in the operational sections of the specifications is not implied. Exposure to absolute maximum rating conditions for extended periods may affect
device reliability.
Package Thermal Characteristics (Note 1)
Junction-to-Ambient Thermal Resistance (θJA)...............71°C/W
Junction-to-Case Thermal Resistance (θJC)....................23°C/W
Note 1: Package thermal resistances were obtained using the method described in JEDEC specification JESD51-7, using a four-layer
board. For detailed information on package thermal considerations, refer to www.maximintegrated.com/thermal-tutorial.
DC Electrical Characteristics
(VDDA - VGNDA = 3.0V to 5.5V, VDDB - VGNDB = 3.0V to 5.5V, TA = TMIN to TMAX, unless otherwise noted. Typical values are at
VDDA - VGNDA = 3.3V, VDDB - VGNDB = 3.3V, VGNDA = VGNDB, and TA = +25°C.) (Notes 2, 3)
PARAMETER
SYMBOL
CONDITIONS
MIN
TYP
MAX
UNITS
POWER
Supply Voltage
VDDA
3.0
5.5
VDDB
3.0
5.5
IDDA
VDDA = 5V, DE = high, RE = TXD =
low, RXD unconnected, no load,
TD1/TD2 unconnected
4.7
IDDB
DE = high, RE = TXD = low, RXD
unconnected, no load, VDDB = 3.3V
7.4
12.5
Supply Current
Undervoltage Lockout
Threshold
Undervoltage Lockout
Threshold Hysteresis
VUVLOA
VUVHYSTA
7.7
mA
RE, RXD, DE, TXD
1.50
1.58
1.65
TD1/TD2 driver
2.55
2.7
2.85
2.55
2.7
2.85
VUVLOB
V
RE, RXD, DE, TXD
50
TD1/TD2 driver
200
VUVHYSTB
V
mV
200
TRANSFORMER DRIVER
Output Resistance
RO
TD1, TD2 Current Limit
ILIM
Switching Frequency
fSW
Duty Cycle
Crossover Dead Time
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TD1/TD2 = low, IOUT = 300mA
0.6
1.5
4.5V ≤ VDDA ≤ 5.5V
540
785
1300
3.0V ≤ VDDA ≤ 3.6V
485
730
1170
350
450
550
Ω
mA
kHz
D
50
%
tDEAD
50
ns
Maxim Integrated │ 2
MAX14853/MAX14855
2.75kVRMS Isolated 500kbps/25Mbps Full-Duplex
RS-485/RS-422 Transceivers with ±35kV ESD
Protection and Integrated Transformer Driver
DC Electrical Characteristics (continued)
(VDDA - VGNDA = 3.0V to 5.5V, VDDB - VGNDB = 3.0V to 5.5V, TA = TMIN to TMAX, unless otherwise noted. Typical values are at
VDDA - VGNDA = 3.3V, VDDB - VGNDB = 3.3V, VGNDA = VGNDB, and TA = +25°C.) (Notes 2, 3)
PARAMETER
SYMBOL
CONDITIONS
MIN
LDO Supply Voltage
VLDO
Relative to GNDB, LDO is on (Note 4)
3.18
LDO Supply Current
ILDO
DE = high, RE = TXD = low, no load,
VLDO = 5.5V
LDO Output Voltage
VDDB
TYP
MAX
UNITS
14
V
7.5
12.9
mA
3.3
3.6
V
LDO
3.0
LDO Current Limit
300
mA
Load Regulation
VLDO = 3.3V, ILOAD = -20mA
0.19
1.7
mV/mA
Line Regulation
VLDO = 3.3V, ILOAD = -20mA
0.12
1.8
mV/V
Dropout Voltage
VLDO = 3.18V, IDDB = -120mA
100
180
mV
Load Capacitance
Nominal value (Note 5)
1
10
µF
0.7 x
VDDA
LOGIC INTERFACE (TXD, RXD, DE, RE)
Input High Voltage
VIH
RE, TXD, DE to GNDA
Input Low Voltage
VIL
RE, TXD, DE to GNDA
VHYS
RE, TXD, DE to GNDA
220
mV
Input Capacitance
CIN
RE, TXD, DE, f = 1MHz
2
pF
Input Pullup Current
IPU
IPD
TXD
-10
-4.5
-1.5
µA
Input Pulldown Current
DE, RE
1.5
4.5
10
µA
Output Voltage High
VOH
RXD to GNDA, IOUT = -4mA
Output Voltage Low
VOL
RXD to GNDA, IOUT = 4mA
Input Hysteresis
0.8
VDDA
-0.4
V
V
0.4
V
6.4
42
mA
0V ≤ VRXD ≤ VDDA, RE = low
5.5
40
mA
0V ≤ VRXD ≤ VDDA, RE = high
-1
+1
µA
Short-Circuit Output Pullup
Current
ISH_PU
0V ≤ VRXD ≤ VDDA, RE = low
Short-Circuit Output Pulldown
Current
ISH_PD
IOZ
Three-State Output Current
V
DRIVER
Differential Driver Output
|VOD|
RL = 54Ω, TXD = high or low,
Figure 1a
RL = 100Ω, TXD = high or low,
Figure 1a
-7V ≤VCM ≤ +12V, Figure 1b
Change in Magnitude of Differential Driver Output Voltage
ΔVOD
RL = 100Ω or 54Ω, Figure 1a (Note 6)
Driver Common-Mode Output
Voltage
VOC
RL = 100Ω or 54Ω, Figure 1a (Note 6)
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1.5
V
2.0
1.5
5
VDDB/
2
0.2
V
3
V
Maxim Integrated │ 3
MAX14853/MAX14855
2.75kVRMS Isolated 500kbps/25Mbps Full-Duplex
RS-485/RS-422 Transceivers with ±35kV ESD
Protection and Integrated Transformer Driver
DC Electrical Characteristics (continued)
(VDDA - VGNDA = 3.0V to 5.5V, VDDB - VGNDB = 3.0V to 5.5V, TA = TMIN to TMAX, unless otherwise noted. Typical values are at
VDDA - VGNDA = 3.3V, VDDB - VGNDB = 3.3V, VGNDA = VGNDB, and TA = +25°C.) (Notes 2, 3)
PARAMETER
Change in Magnitude of
Common-Mode Voltage
SYMBOL
CONDITIONS
ΔVOC
RL = 100Ω or 54Ω, Figure 1a (Note 5)
MIN
TYP
MAX
UNITS
0.2
V
GNDB ≤ VOUT ≤ +12V, output low
(Note 7)
+30
+250
-7V ≤ VOUT ≤ VDDB, output high
(Note 7)
-250
-30
Driver Short-Circuit Output
Current
IOSD
Single-Ended Driver Output
Voltage High
VOH
Y and Z outputs, IY,Z = -20mA
Single-Ended Driver Output
Voltage Low
VOL
Y and Z outputs, IY,Z = +20mA
Differential Driver Output
Capacitance
COD
DE = RE = high, f = 4MHz
Input Current (A and B)
IA, IB
DE = GNDA,
VDDB = VGNDB
or 3.6V
Receiver Differential Threshold
Voltage
VTH
-7V ≤ VCM ≤ +12V
mA
2.2
V
0.8
12
V
pF
RECEIVER
VIN = +12V
VIN = -7V
Receiver Input Hysteresis
ΔVTH
Receiver Input Resistance
RIN
-7V ≤ VCM ≤ +12V, DE = low
CA,B
Measured between A and B,
DE = RE = GNDA at 2MHz
Differential Input Capacitance
+250
-200
-200
VCM = 0V
-120
20
48
-10
µA
mV
mV
kΩ
12
pF
+160
°C
15
°C
PROTECTION
Thermal-Shutdown Threshold
TSHDN
Thermal-Shutdown Hysteresis
THYST
Temperature rising
Human Body Model
±35
IEC 61000-4-2 Air-Gap Discharge to
GND
±18
IEC 61000-4-2- Contact Discharge to
GND
±8
ESD Protection
(A, B, Y, Z, GNDB Pins to
GNDA)
Human Body Model
±8
kV
ESD Protection (All Other Pins)
Human Body Model
±4
kV
ESD Protection
(A, B, Y, Z Pins to GNDB)
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kV
Maxim Integrated │ 4
MAX14853/MAX14855
2.75kVRMS Isolated 500kbps/25Mbps Full-Duplex
RS-485/RS-422 Transceivers with ±35kV ESD
Protection and Integrated Transformer Driver
Switching Electrical Characteristics (MAX14853)
(VDDA - VGNDA = 3.0V to 5.5V, VDDB - VGNDB = 3.0V to 5.5V, TA = TMIN to TMAX, unless otherwise noted. Typical values are at
VDDA - VGNDA = 3.3V, VDDB - VGNDB = 3.3V, VGNDA = VGNDB, and TA = +25°C.) (Note 5)
PARAMETER
SYMBOL
CONDITIONS
MIN
TYP
MAX
UNITS
DYNAMIC
Common-Mode Transient
Immunity
CMTI
Glitch Rejection
(Note 8)
TXD, DE, RXD
35
10
17
kV/μs
29
ns
RL = 54Ω, CL = 50pF, Figure 2 and
tDPLH, tDPHL
Figure 3
1040
ns
DRIVER
Driver Propagation Delay
Differential Driver Output Skew
|tDPLH - tDPHL|
tDSKEW
RL = 54Ω, CL = 50pF, Figure 2 and
Figure 3
144
ns
Driver Differential Output Rise
or Fall Time
tLH, tHL
RL = 54Ω, CL = 50pF, Figure 2 and
Figure 3
900
ns
Maximum Data Rate
DRMAX
Driver Enable to Output High
Driver Enable to Output Low
Driver Disable Time From Low
Driver Disable Time From High
500
kbps
tDZH
tDZL
RL = 110Ω, CL = 50pF, Figure 4
2540
ns
RL = 110Ω, CL = 50pF, Figure 5
2540
ns
tDLZ
tDHZ
RL = 110Ω, CL = 50pF, Figure 5
140
ns
RL = 110Ω, CL = 50pF, Figure 4
140
ns
CL = 15pF, Figure 6 and Figure 7
tRPLH, tRPHL
(Note 9)
240
ns
CL = 15pF, Figure 6 and Figure 7
(Note 9)
34
ns
RECEIVER
Receiver Propagation Delay
Receiver Output Skew
tRSKEW
Maximum Data Rate
DRMAX
500
kbps
Receiver Enable to Output
High
tRZH
RL = 1kΩ, CL = 15pF, S2 closed,
Figure 8
20
ns
Receiver Enable to Output Low
tRZL
RL = 1kΩ, CL = 15pF, S1 closed,
Figure 8
30
ns
Receiver Disable Time From
Low
tRLZ
RL = 1kΩ, CL = 15pF, S1 closed,
Figure 8
20
ns
Receiver Disable Time From
High
tRHZ
RL = 1kΩ, CL = 15pF, S2 closed,
Figure 8
20
ns
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Maxim Integrated │ 5
MAX14853/MAX14855
2.75kVRMS Isolated 500kbps/25Mbps Full-Duplex
RS-485/RS-422 Transceivers with ±35kV ESD
Protection and Integrated Transformer Driver
Switching Electrical Characteristics (MAX14855)
(VDDA - VGNDA = 3.0V to 5.5V, VDDB - VGNDB = 3.0V to 5.5V, TA = TMIN to TMAX, unless otherwise noted. Typical values are at
VDDA - VGNDA = 3.3V, VDDB - VGNDB = 3.3V, VGNDA = VGNDB, and TA = +25°C.) (Note 5)
PARAMETER
DYNAMIC
Common-Mode Transient
Immunity
Glitch Rejection
DRIVER
Driver Propagation Delay
SYMBOL
CMTI
CONDITIONS
MIN
(Note 8)
TXD, DE, RXD
TYP
MAX
35
10
17
UNITS
kV/μs
29
ns
RL = 54Ω, CL = 50pF, Figure 2 and
tDPLH, tDPHL
Figure 3
65
ns
Differential Driver Output Skew
|tDPLH - tDPHL|
tDSKEW
RL = 54Ω, CL = 50pF, Figure 2 and
Figure 3
7
ns
Driver Differential Output Rise
or Fall Time
tLH, tHL
RL = 54Ω, CL = 50pF, Figure 2 and
Figure 3
10
ns
Maximum Data Rate
DRMAX
Driver Enable to Output High
Driver Enable to Output Low
Driver Disable Time from Low
Driver Disable Time from High
RECEIVER
Receiver Propagation Delay
Mbps
tDZH
tDZL
RL = 110Ω, CL = 50pF, Figure 4
80
ns
RL = 110Ω, CL = 50pF, Figure 5
80
ns
tDLZ
tDHZ
RL = 110Ω, CL = 50pF, Figure 5
80
ns
RL = 110Ω, CL = 50pF, Figure 4
80
ns
CL = 15pF, Figure 6 and Figure 7
tRPLH, tRPHL
(Note 9)
65
ns
CL = 15pF, Figure 6 and Figure 7
(Note 9)
7
ns
Receiver Output Skew
tRSKEW
Maximum Data Rate
DRMAX
Receiver Enable to Output
High
25
25
Mbps
Receiver Enable to Output Low
tRZL
RL = 1kΩ, CL = 15pF, S2 closed,
Figure 8
RL = 1kΩ, CL = 15pF, S1 closed,
Figure 8
Receiver Disable Time from
Low
tRLZ
RL = 1kΩ, CL = 15pF, S1 closed,
Figure 8
20
ns
Receiver Disable Time from
High
tRHZ
RL = 1kΩ, CL = 15pF, S2 closed,
Figure 8
20
ns
tRZH
20
ns
30
ns
Note 2: All devices are 100% production tested at TA = +25°C. Specifications over temperature are guaranteed by design.
Note 3: All currents into the device are positive. All currents out of the device are negative. All voltages are referenced to their
respective ground (GNDA or GNDB), unless otherwise noted.
Note 4:VLDO max indicates voltage capability of the circuit. Power dissipation requirements may limit VLDO max to a lower value.
Note 5: Not production tested. Guaranteed by design.
Note 6: ΔVOD and ΔVOC are the changes in VOD and VOC, respectively, when the TXD input changes state.
Note 7: The short-circuit output current applies to the peak current just prior to current limiting.
Note 8: CMTI is the maximum sustainable common-mode voltage slew rate while maintaining the correct output states. CMTI
applies to both rising and falling common-mode voltage edges. Tested with the transient generator connected between
GNDA and GNDB.
Note 9: Capacitive load includes test probe and fixture capacitance.
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Maxim Integrated │ 6
MAX14853/MAX14855
2.75kVRMS Isolated 500kbps/25Mbps Full-Duplex
RS-485/RS-422 Transceivers with ±35kV ESD
Protection and Integrated Transformer Driver
Insulation Characteristics
PARAMETER
Partial DischargeTest Voltage
SYMBOL
VPR
CONDITIONS
VALUE
UNITS
Method B1 = VIORM x 1.875 (t = 1s,
partial discharge < 5pC)
1182
VP
Maximum Repetitive Peak Isolation
Voltage
VIORM
(Note 10)
630
VP
Maximum Working Isolation Voltage
VIOWM
(Note 10)
445
VRMS
Maximum Transient Isolation Voltage
VIOTM
t = 1s
4600
VP
Maximum Withstand Isolation Voltage
VISO
VIOSM
t = 60s, f = 60Hz (Notes 10, 11)
2750
10
VRMS
kV
>109
Ω
Maximum Surge Isolation Voltage
Insulation Resistance
Basic insulation
RS
TA = +150°C, VIO = 500V
Barrier Capacitance Input-to-Output
CIO
f = 1MHz
2
pF
Minimum Creepage Distance
CPG
Wide SO
8
mm
Minimum Clearance Distance
CLR
Wide SO
8
mm
0.015
mm
Internal Clearance
Comparative Tracking Resistance Index
Distance through insulation
CTI
Material Group II (IEC 60112)
Climatic Category
Pollution Degree (DIN VDE 0110, Table 1)
575
40/125/21
2
Note 10:VIORM, VIOWM, and VISO are defined by the IEC 60747-5-5 standard.
Note 11:Product is qualified VISO for 60 seconds. 100% production tested at 120% of VISO for 1s.
Safety Regulatory Approvals (Pending)
UL
The MAX14853/MAX14855 is certified under UL1577. For more details, see file E351759.
Rate up to 2750VRMS isolation voltage for basic insulation.
cUL
Pending
VDE
Pending
TUV
Pending
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Maxim Integrated │ 7
MAX14853/MAX14855
2.75kVRMS Isolated 500kbps/25Mbps Full-Duplex
RS-485/RS-422 Transceivers with ±35kV ESD
Protection and Integrated Transformer Driver
375Ω
Y
Y
RL
2
VOD
VOD
RL
2
60Ω
+ VCM
-
VOC
Z
Z
375Ω
(b)
(a)
Figure 1. Driver DC Test Load
Y
TXD
Z
VOD
RL
CL
GNDA
Figure 2. Driver Timing Test Circuit
tLH P 3ns, tHL P 3ns
VDDA
50%
TXD
50%
GNDA
1/2 VO
tDPHL
tDPLH
Z
Y
1/2 VO
VO
VDIFF = VY - VZ
VO
80%
80%
VDIFF
0
20%
20%
tLH
-VO
tHL
tDSKEW = |tDPLH - tDPHL|
Figure 3. Driver Propagation Delays
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Maxim Integrated │ 8
MAX14853/MAX14855
Y
GNDA OR VDDA TXD D
Z
DE
2.75kVRMS Isolated 500kbps/25Mbps Full-Duplex
RS-485/RS-422 Transceivers with ±35kV ESD
Protection and Integrated Transformer Driver
S1
VDDA
OUT
CL
50pF
DE
RL = 500I
50%
250mV
OUT
GENERATOR
50%
GNDB
50I
GNDA
tDZH
tDHZ
VOH
GNDB
GNDA
Figure 4. Driver Enable and Disable Times (tDZH, tDHZ)
VDDB
GNDA OR VDDA TXD D
Y
Z
DE
GENERATOR
RL = 500I
S1
OUT
CL = 50pF
GNDB
50I
GNDA
VDDA
DE
50%
GNDA
tDZL
tDLZ
VDDB
50%
OUT
250mV
VOL
Figure 5. Driver Enable and Disable Times (tDZL, tDLZ)
A
ATE
R
VID
RECEIVER
OUTPUT
B
Figure 6. Receiver Propagation Delay Test Circuit
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Maxim Integrated │ 9
MAX14853/MAX14855
2.75kVRMS Isolated 500kbps/25Mbps Full-Duplex
RS-485/RS-422 Transceivers with ±35kV ESD
Protection and Integrated Transformer Driver
t = 1MHz, tLH P 3ns, tHL P 3ns
A
1V
B
-1V
tRPHL
tRPLH
VDDA
2
RXD
VOH
VDDA
2
VOL
tRSKEW = |tRPHL - tRPLH|
Figure 7. Receiver Propagation Delays
+1.5V
S3
-1.5V
VID
GNDB
GENERATOR
R
RE
RXD
RL
1kI
S1
VDDA
S2
CL
15pF
GNDA
50I
GNDA
VDDA
VDDA
50%
RE
S1 OPEN
S2 CLOSED
GNDA S3 = +1.5V
50%
RE
GNDA
tRZL
tRZH
VOH
VDDA
2
GNDA
RXD
VDDA
50%
RE
VDDA
2
RXD
S1 OPEN
S2 CLOSED
S3 = +1.5V
VDDA
RE
50%
GNDA
GNDA
RXD
VDDA
VOL
S1 CLOSED
S2 OPEN
S3 = -1.5V
tRLZ
tRHZ
0.25V
S1 CLOSED
S2 OPEN
S3 = -1.5V
VDDA
VOH
RXD
GNDA
0.25V
VOL
Figure 8. Receiver Enable and Disable Times
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Maxim Integrated │ 10
MAX14853/MAX14855
2.75kVRMS Isolated 500kbps/25Mbps Full-Duplex
RS-485/RS-422 Transceivers with ±35kV ESD
Protection and Integrated Transformer Driver
Typical Operating Characteristics
(VDDA – VGNDA = 3.3V, VDDB – VGNDB = 3.3V, VGNDA = VGNDB, and TA = +25°C, unless otherwise noted.)
VDDA SUPPLY CURRENT
vs. TEMPERATURE
8
toc01
14
7
3.5
8
6
3
NO LOAD
NO SWITCHING
TD1/TD2 UNCONNECTED
-45 -30 -15
0
15
30
45
60
75
0
90 105
NO LOAD
NO SWITCHING
-45 -30 -15
TEMPERATURE (°C)
240
220
0
15
30
45
800
700
tPDHL
500
400
tPDLH
200
100
0
15
30
45
60
75
0.0
90 105
60
75
1000
C L = 15pF
-45 -30 -15
180
160
140
120
100
tRPLH
80
60
90 105
0
-45 -30 -15
0
15
30
45
60
75
45
60
75
90 105
800
700
600
tDZH
tDZL
500
400
300
200
0
90 105
tDHZ
tDLZ
-45 -30 -15
toc08
VOUTN
RXD
2V/div
VINSIDE
0V
0V
VBACKUP
Y
1V/div
B
1V/div
Z
1V/div
A
1V/div
PROPAGATION DELAY (ns)
C L = 15pF
100ns/div
0
15
30
45
60
75
90 105
TEMPERATURE (°C)
TXD
2V/div
R L = 54Ω
C L = 50pF
30
100
MAX14853 RECEIVER
PROPAGATION DELAY
toc07
15
MAX14853 DRIVER ENABLE/DISABLE
DELAY vs. TEMPERATURE toc06
TEMPERATURE (°C)
MAX14853 DRIVER
PROPAGATION DELAY
0
900
tRPHL
20
TEMPERATURE (°C)
100ns/div
54Ω LOAD
TEMPERATURE (°C)
40
R L = 54Ω
C L = 50pF
-45 -30 -15
120Ω LOAD
0.5
MAX14853 RECEIVER PROPAGATION
DELAY vs. TEMPERATURE
toc05
200
PROPAGATION DELAY (ns)
PROPAGATION DELAY (ns)
900
300
2.0
TEMPERATURE (°C)
MAX14853 TRANSMITTER PROPAGATION
DELAY vs. TEMPERATURE
toc04
600
2.5
1.0
2
ENABLE/DISABLE DELAY (ns)
1
toc03
NO LOAD
1.5
4
2
DIFFERENTIAL OUTPUT VOLTAGE
vs. TEMPERATURE
3.0
VOD (V)
IDDB (mA)
IDDA (mA)
4
0
4.0
10
5
1000
toc02
12
6
0
VDDB SUPPLY CURRENT
vs. TEMPERATURE
65
60
55
50
45
40
35
30
25
20
15
10
5
0
MAX14855 TRANSMITTER PROPAGATION
DELAY vs. TEMPERATURE
toc09
tPDHL
tPDLH
R L = 54Ω
C L = 50pF
-45 -30 -15
0
15
30
45
60
75
90 105
TEMPERATURE (°C)
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Maxim Integrated │ 11
MAX14853/MAX14855
2.75kVRMS Isolated 500kbps/25Mbps Full-Duplex
RS-485/RS-422 Transceivers with ±35kV ESD
Protection and Integrated Transformer Driver
Typical Operating Characteristics (continued)
65
60
55
50
45
40
35
30
25
20
15
10
5
0
MAX14855 RECEIVER PROPAGATION
DELAY vs. TEMPERATURE
toc10
MAX14855 DRIVER ENABLE/DISABLE
DELAY vs. TEMPERATURE toc11
80
70
ENABLE/DISABLE DELAY (ns)
PROPAGATION DELAY (ns)
(VDDA – VGNDA = 3.3V, VDDB – VGNDB = 3.3V, VGNDA = VGNDB, and TA = +25°C, unless otherwise noted.)
tRPHL
tRPLH
0
15
30
45
60
75
50
40
30
tDZL
tDLZ
20
10
C L = 15pF
-45 -30 -15
tDZH
tDHZ
60
0
90 105
-45 -30 -15
0
TEMPERATURE (°C)
15
30
45
60
75
90 105
TEMPERATURE (°C)
MAX14855 DRIVER
PROPAGATION DELAY
MAX14855 RECEIVER
PROPAGATION DELAY
toc12
toc13
R L = 54Ω
C L = 50pF
TXD
2V/div
VOUTN
0V
VINSIDE
Y
1V/div
VBACKUP
A
1V/div
VOUTN
VINSIDE
B
1V/div
VBACKUP
RXD
2V/div
0V
Z
1V/div
C L = 15pF
10ns/div
10ns/div
RECEIVER ENABLE/DISABLE
DELAY vs. TEMPERATURE
20
toc14
7
16
14
tRZL
12
tRZH
tRHZ
10
toc15
54Ω LOAD
120Ω LOAD
6
5
tRLZ
IDDA (mA)
ENABLE/DISABLE DELAY (ns)
18
8
6
4
3
2
4
1
2
0
VDDA SUPPLY CURRENT
vs. DATA RATE
8
-45 -30 -15
0
15
30
45
60
TEMPERATURE (°C)
www.maximintegrated.com
75
90 105
0
0.01
0.1
1
10
100
DATA RATE (Mbps)
Maxim Integrated │ 12
MAX14853/MAX14855
2.75kVRMS Isolated 500kbps/25Mbps Full-Duplex
RS-485/RS-422 Transceivers with ±35kV ESD
Protection and Integrated Transformer Driver
Typical Operating Characteristics (continued)
(VDDA – VGNDA = 3.3V, VDDB – VGNDB = 3.3V, VGNDA = VGNDB, and TA = +25°C, unless otherwise noted.)
VDDB SUPPLY
CURRENT vs. DATA RATE
70
toc16
54Ω LOAD
50
IDDB (mA)
SWITCHING FREQUENCY (kHz)
60
40
30
20
120Ω LOAD
10
0
600
TRANSFORMER DRIVER SWITCHING
FREQUENCY vs. TEMPERATURE toc17
550
500
450
400
350
NO LOAD
0.01
0.1
1
10
100
300
-45 -30 -15
DATA RATE (Mbps)
15
30
45
60
75
90 105
TEMPERATURE (°C)
TD1/TD2 VOLTAGE
vs. DRIVE CURRENT
400
0
TRANSFORMER DRIVER
toc18
toc19
TD1/TD2 DRIVER VOLTAGE (mV)
350
300
VOUTN
250
VINSIDE
200
TD1 & TD2
2V/div
VBACKUP
150
0V
100
50
0
100mA LOAD ON VDDB
0
100
200
300
400
500
600
700
400ns/div
DRIVER CURRENT (mA)
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Maxim Integrated │ 13
MAX14853/MAX14855
2.75kVRMS Isolated 500kbps/25Mbps Full-Duplex
RS-485/RS-422 Transceivers with ±35kV ESD
Protection and Integrated Transformer Driver
Pin Configuration
TOP VIEW
+
TD1
1
16 VDDB
TD2
2
GNDA
3
VDDA
4
13 B
RXD
5
12 Z
RE
6
11 Y
DE
7
10 VLDO
TXD
8
9
MAX14853
MAX14855
15 GNDB
14 A
GNDB
SOIC
Pin Description
PIN
NAME
REFERENCE
1
TD1
GNDA
Transformer Driver Output 1
2
TD2
GNDA
Transformer Driver Output 2
3
GNDA
—
4
VDDA
GNDA
UART/Logic-Side Power Input. Bypass VDDA to GNDA with both 0.1μF and 1µF capacitors
as close as possible to the device.
5
RXD
GNDA
Receiver Data Output. Drive RE low to enable RXD. With RE low, RXD is high when
(VA - VB) > -10mV and is low when (VA - VB) < -200mV. RXD is high when VDDB is less
than VUVLOB. RXD is high impedance when RE is high.
6
RE
GNDA
Receiver Output Enable. Drive RE low or connect to GNDA to enable RXD. Drive RE high
to disable RXD. RXD is high impedance when RE is high. RE has an internal 4.5µA pulldown to GNDA.
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FUNCTION
UART/Logic-Side Ground. GNDA is the ground reference for digital signals and the
transformer driver.
Maxim Integrated │ 14
MAX14853/MAX14855
2.75kVRMS Isolated 500kbps/25Mbps Full-Duplex
RS-485/RS-422 Transceivers with ±35kV ESD
Protection and Integrated Transformer Driver
Pin Description (continued)
PIN
NAME
REFERENCE
FUNCTION
7
DE
GNDA
Driver Output Enable. Drive DE high to enable bus driver outputs Y and Z. Drive DE low or
connect to GNDA to disable Y and Z. Y and Z are high impedance when DE is low. DE has
an internal 4.5µA pulldown to GNDA.
8
TXD
GNDA
Driver Input. With DE high, a low on TXD forces the noninverting output (Y) low and the
inverting output (Z) high. Similarly, a high on TXD forces the noninverting output high and
the inverting output low. TXD has an internal 4.5µA pullup to VDDA.
9, 15
GNDB
—
Cable-Side Ground. GNDB is the ground reference for the internal LDO and the RS-485/
RS-422 bus signals.
10
VLDO
GNDB
LDO Power Input. Connect a minimum voltage of 3.18V to VLDO to power the cable-side
of the transceiver. Bypass VLDO to GNDB with both 0.1μF and 1µF capacitors as close as
possible to the device. To disable the internal LDO, leave VLDO unconnected or connect to
GNDB.
11
Y
GNDB
Noninverting Driver Output
12
Z
GNDB
Inverting Driver Output
13
B
GNDB
Inverting Receiver Input
14
A
GNDB
Noninverting Receiver Input
GNDB
Cable-Side Power Input/Isolated LDO Power Output. Bypass VDDB to GNDB with both
0.1μF and 1μF capacitors as close as possible to the device. VDDB is the output of the
internal LDO when power is applied to VLDO. When the internal LDO is not used (VLDO is
unconnected or connected to GNDB), VDDB is the positive supply input for the cable-side
of the IC.
16
VDDB
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Maxim Integrated │ 15
MAX14853/MAX14855
2.75kVRMS Isolated 500kbps/25Mbps Full-Duplex
RS-485/RS-422 Transceivers with ±35kV ESD
Protection and Integrated Transformer Driver
Function Tables
TRANSMITTING
INPUTS
OUTPUTS
VDDA
VDDB
DE
TXD
Y
Z
≥ VUVLOA
≥ VUVLOB
1
1
1
0
≥ VUVLOA
≥ VUVLOB
1
0
0
1
≥ VUVLOA
≥ VUVLOB
0
X
High-Z
High-Z
< VUVLOA
≥ VUVLOB
X
X
High-Z
High-Z
≥ VUVLOA
< VUVLOB
X
X
High-Z
High-Z
< VUVLOA
< VUVLOB
X
X
High-Z
High-Z
Note: Drive DE low to disable the transmitter outputs. Drive DE high to enable the transmitter outputs. DE has an internal pulldown
to GNDA.
X = Don’t care.
RECEIVING
INPUTS
OUTPUTS
VDDA
VDDB
RE
(VA - VB)
RXD
≥ VUVLOA
≥ VUVLOB
0
> -10mV
1
≥ VUVLOA
≥ VUVLOB
0
< -200mV
0
≥ VUVLOA
≥ VUVLOB
0
Open/Short
1
≥ VUVLOA
≥ VUVLOB
1
X
High-Z
< VUVLOA
≥ VUVLOB
X
X
High-Z
≥ VUVLOA
< VUVLOB
0
X
1
< VUVLOA
< VUVLOB
X
X
High-Z
Note: Drive RE high to disable the receiver output. Drive RE low to enable to receiver output. RE has an internal pulldown to GNDA.
X = Don’t care.
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Maxim Integrated │ 16
MAX14853/MAX14855
2.75kVRMS Isolated 500kbps/25Mbps Full-Duplex
RS-485/RS-422 Transceivers with ±35kV ESD
Protection and Integrated Transformer Driver
Detailed Description
Driver Output Protection
The MAX14853/MAX14855 isolated RS-485/RS-422
transceivers provide 2750VRMS (60s) of galvanic
isolation between the RS-485/RS-422 cable-side of the
transceiver and the UART-side. These devices allow
up to 500kbps (MAX14853) or 25Mbps (MAX14855)
communication across an isolation barrier when a large
potential exists between grounds on each side of the
barrier.
Two mechanisms prevent excessive output current and
power dissipation caused by faults or by bus contention.
The first, a current limit on the output stage, provides
immediate protection against short circuits over the entire
common-mode voltage range. The second, a thermal-shutdown circuit, forces the driver outputs into a high-impedance state if the die temperature exceeds +160°C (typ).
Isolation
The MAX14853/MAX14855 are protected from overtemperature damage by integrated thermal-shutdown circuitry.
When the junction temperature (TJ) exceeds +160°C (typ),
the driver outputs go high impedance. The device resumes
normal operation when TJ falls below +145°C (typ).
To achieve power isolation, the MAX14853/MAX14855
feature an integrated transformer driver to drive an external
center-tapped transformer, allowing the transfer of operating
power from the UART-side across the isolation barrier to
the cable-side. Connect the primary side of the external
transformer to the MAX14853/MAX14855’s transformer
driver outputs (TD1 and TD2).
Transformer Driver
Both data and power can be transmitted across the isolation
barrier. Data isolation is achieved using integrated capacitive
isolation that allows data transmission between the UARTside and the cable-side of the transceiver.
The MAX14853 and features a slew-rate limited driver that
minimizes EMI and reduces reflections caused by improperly
terminated cables, allowing error-free data transmission at
data rates up to 500kbps. The MAX14853also includes an
added deglitch filter on the receiver signal path for enhanced
noise immunity when differential signals have very slow rise
and fall times.
Integrated LDO
The MAX14853/MAX14855 include an internal low-dropout
regulator with a set 3.3V (typ) output that is used to power
the cable-side of the IC. The output of the LDO is VDDB.
The LDO has a 300mA (typ) current limit. If the LDO is
unused, connect VLDO to GNDB and apply +3.3V directly
to VDDB.
True Fail-Safe
The MAX14853/MAX14855 guarantee a logic-high on the
receiver output when the receiver inputs are shorted or
open, or when connected to a terminated transmission line
with all drivers disabled. The receiver threshold is fixed
between -10mV and -200mV. If the differential receiver input
voltage (VA - VB) is greater than or equal to -10mV, RXD
is logic high. In the case of a terminated bus with all
transmitters disabled, the receiver’s differential input voltage
is pulled to zero by the termination resistors. Due to the
receiver thresholds of the MAX14853/MAX14855, this
results in a logic-high at RXD.
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Thermal Shutdown
Overcurrent Limiting
The MAX14853/MAX14855 feature overcurrent limiting
to protect the integrated transformer driver from excessive
currents when charging large capacitive loads or
driving into short-circuits. Current limiting is achieved in
two stages: internal circuitry monitors the output current
and detects when the peak current rises above 1.2A.
When the 1.2A threshold is exceeded, internal circuitry
reduces the output current to the 730mA current-limit.
The MAX14853/MAX14855 monitor the driver current on
a cycle-by-cycle basis and limit the current until the short
is removed.
The transformer driver on the MAX14853/MAX14855 can
dissipate large amounts of power during overcurrent limiting,
causing the IC to enter thermal shutdown.
Transformer Selection
The integrated push-pull transformer driver allows the
transmission of operating power from the logic side, across
the isolation barrier, to the isolated field side of the device.
The 450kHz transformer driver operates with center-tapped
primary and secondary transformers. Select a transformer
with an ET product greater than or equal to the ET of the
driver to ensure that the transformer does not enter saturation. E is the voltage applied to the transformer and T is the
maximum time it is applied during any one cycle. Calculate
the minimum ET product for the transformer primary as:
ET = VMAX/(2 x fMIN)
Where VMAX is the worst-case maximum supply voltage
on VDDA and fMIN is the minimum frequency at that supply
voltage. For example, using 5.5V and 350kHz, the
required minimum ET product is 7.9Vµs.
Maxim Integrated │ 17
MAX14853/MAX14855
2.75kVRMS Isolated 500kbps/25Mbps Full-Duplex
RS-485/RS-422 Transceivers with ±35kV ESD
Protection and Integrated Transformer Driver
Applications Information
Extended ESD Protection
128 Transceivers on the Bus
The standard RS-485 receiver input impedance is one unit
load, and a standard driver can drive up to 32 unit loads.
The MAX14853/MAX14855 transceivers have a ¼-unit
load receiver, allowing up to 128 transceivers connected
in parallel on one communication line. Connect any combination of these devices, and/or other RS-485 devices, for
a maximum of 32 unit loads to the line.
Typical Application
The MAX14853/MAX14855 full-duplex transceivers are
designed for bidirectional data communications on multipoint bus transmission lines. Figure 9 and Figure 10 show
typical network applications circuits. To minimize reflections,
the bus should be terminated at the receiver input in its
characteristics impedance, and stub lengths off the main
line should be kept as short as possible.
Layout Considerations
It is recommended to design an isolation or keep-out
channel underneath the isolator that is free from ground
and signal planes. Any galvanic or metallic connection
between the cable-side and UART-side defeats the
isolation.
ESD protection structures are incorporated on all pins
to protect against electrostatic discharge encountered
during handling and assembly. The driver outputs and
receiver inputs of the MAX14853/MAX14855 have extra
protection against static electricity. The ESD structures
withstand high ESD in normal operation and when powered down. After an ESD event, the devices keep working
without latch-up or damage.
Bypass VDDA to GNDA and bypass VDDB and VLDO
to GNDB with both 0.1μF and 1μF capacitors to ensure
maximum ESD protection.
ESD protection can be tested in various ways. The
transmitter outputs and receiver inputs of the MAX14853/
MAX14855 are characterized for protection to the cableside ground (GNDB) to the following limits:
●●
±35kV HBM
●●
±18kV using the Air-Gap Discharge method specified
in IEC 61000-4-2
●●
±8kV using the Contact Discharge method specified
in the IEC 61000-4-2
The transmitter outputs and receiver inputs also include
extended ESD protection with reference to the UART-side
ground (GNDA) to the following limits:
Ensure that the decoupling capacitors between VDDA and
GNDA and between VLDO, VDDB, and GNDB are located
as close as possible to the IC to minimize inductance.
●●
±8kV HBM
Route important signal lines close to the ground plane to minimize possible external influences. On the cable-side of the
MAX14853/MAX14855, it is good practice to have the bus
connectors and termination resistor as close as possible
to the A and B pins.
Table 1. Recommended Transformers
MANUFACTURER
PART NUMBER
APPLICATION
CONFIGURATION
ISOLATION
(VRMS)
DIMENSIONS
(L x W x H) (mm)
HALO TGMS-1440V6LF
5V to 5V
1CT: 1.33CT
2750
9.45 x 10.87 x 10.03
HALO TGMS-1464V6LF
3.3V to 5V
1CT: 2.4CT
2750
9.45 x 10.87 x 10.03
WURTH 750315225
5V to 5V
1CT: 1.1CT
2750
6.73 x 7.14 x 4.19
WURTH 750315226
5V to 5V
1CT: 1.3CT
2750
6.73 x 7.14 x 4.19
WURTH 750315227
3.3V to 5V
1CT: 1.7CT
2750
6.73 x 7.14 x 4.19
WURTH 750315228
3.3V to 5V
1CT: 2CT
2750
6.73 x 7.14 x 4.19
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Maxim Integrated │ 18
MAX14853/MAX14855
2.75kVRMS Isolated 500kbps/25Mbps Full-Duplex
RS-485/RS-422 Transceivers with ±35kV ESD
Protection and Integrated Transformer Driver
Slave
RXD
RE
TXD
DE
Y
A
120Ω
Z
B
B
A
B
RS-485 TRANSCEIVER
RXD
RS-485 TRANSCEIVER
RS-485 TRANSCEIVER
Master
RE
TXD
DE
A
RS-485 TRANSCEIVER
MAX14853
MAX14855
INTEGRATED
ISOLATION BARRIER
Slave
DE
TXD
RE
RXD
DE
TXD RE
Slave
RXD
Figure 9. Typical Isolated Full-Duplex RS-485/RS-422 Application
VDDA
10µF
1µF
VDDA
2
3
VDDB
VDDB
RXD
RE
TXD
DE
A
0.1µF
2
2
0.1µF
3
3
VLDO
TD2
TD1
VDDA
1µF
3
Y
B
Z
Y
A
Z
B
MAX14853
MAX14855
1
4
1µF 0.1µF
0.1µF
1µF
RS-485 TRANSCEIVER
1
2
VLDO
TD2
10µF
3
2
RS-485 TRANSCEIVER
1
1
TD1
1µF
3
2
2
VDDA
10µF
10µF
1µF
4
0.1µF
4
RXD
RE
TXD
DE
MAX14853
MAX14855
3
4
Figure 10. Typical Isolated RS-485/RS-422 Application with Integrated Transformer Driver
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Maxim Integrated │ 19
MAX14853/MAX14855
2.75kVRMS Isolated 500kbps/25Mbps Full-Duplex
RS-485/RS-422 Transceivers with ±35kV ESD
Protection and Integrated Transformer Driver
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 (HBM)
Figure 11 shows the HBM test model and Figure 12
shows the current waveform it generates when discharged in a low-impedance state. This model consists of
a 100pF capacitor charged to the ESD voltage of interest,
which is then discharged in to the test device through a
1.5kΩ resistor.
The major difference between tests done using the HBM
and IEC 61000-4-2 is higher peak current in IEC 610004-2 because series resistance is lower in the IEC 610004-2 model. Hence, the ESD withstand voltage measured
to IEC 61000-4-2 is generally lower than that measured
using the HBM. Figure 13 shows the IEC 61000-4-2
model and Figure 14 shows the current waveform for IEC
61000-4-2 ESD Contact Discharge Test.
IEC 61000-4-2
The IEC 61000-4-2 standard covers ESD testing and
performance of finished equipment. However, it does not
specifically refer to integrated circuits. The MAX14853/
MAX14855 help in designing equipment to meet IEC
61000-4-2 without the need for additional ESD protection
components.
RC
1MΩ
CHARGE-CURRENTLIMIT RESISTOR
HIGHVOLTAGE
DC
SOURCE
Cs
100pF
RD
1500Ω
IP 100%
90%
DISCHARGE
RESISTANCE
STORAGE
CAPACITOR
Ir
AMPS
DEVICE
UNDER
TEST
36.8%
10%
0
0
Figure 11. Human Body ESD Test Model
CHARGE-CURRENTLIMIT RESISTOR
HIGHVOLTAGE
DC
SOURCE
Cs
150pF
tDL
CURRENT WAVEFORM
Figure 12. Human Body Current Waveform
RD
330Ω
I
100%
90%
DISCHARGE
RESISTANCE
STORAGE
CAPACITOR
TIME
tRL
IPEAK
RC
50MΩ TO 100MΩ
PEAK-TO-PEAK RINGING
(NOT DRAWN TO SCALE)
DEVICE
UNDER
TEST
10%
tr = 0.7ns TO 1ns
t
30ns
60ns
Figure 13. IEC 61000-4-2 ESD Test Model
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Figure 14. IEC 61000-4-2 ESD Generator Current Waveform
Maxim Integrated │ 20
MAX14853/MAX14855
2.75kVRMS Isolated 500kbps/25Mbps Full-Duplex
RS-485/RS-422 Transceivers with ±35kV ESD
Protection and Integrated Transformer Driver
Typical Application Circuit
VDDA
TD1
VDDA
VLDO
TD2
XFMR
DRIVER
VDDB
LDO
A
µC
RS-485
TRANSCEIVER
RXD
RE
TXD
DE
MAX14853
MAX14855
GNDA
B
Z
Y
GNDB
ISOLATION BARRIER
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Maxim Integrated │ 21
MAX14853/MAX14855
2.75kVRMS Isolated 500kbps/25Mbps Full-Duplex
RS-485/RS-422 Transceivers with ±35kV ESD
Protection and Integrated Transformer Driver
Ordering Information
DATA RATE (MAX)
DRIVER SLEW RATE
LIMITED
RECEIVER
DEGLITCHING
TEMP RANGE
PIN-PACKAGE
MAX14853GWE+
500kbps
YES
YES
-40°C to +105°C
16 SOIC (W)
MAX14853GWE+T
500kbps
YES
YES
-40°C to +105°C
16 SOIC (W)
MAX14855GWE+
25Mbps
NO
NO
-40°C to +105°C
16 SOIC (W)
MAX14855GWE+T
25Mbps
NO
NO
-40°C to +105°C
16 SOIC (W)
PART
+Denotes a lead(Pb)-free/RoHS-compliant package.
T = Tape and Reel
Chip Information
PROCESS: BiCMOS
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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.
PACKAGE
TYPE
PACKAGE
CODE
OUTLINE
NO.
LAND PATTERN
NO.
16 SOIC
W16M+10
21-0042
90-0107
Maxim Integrated │ 22
MAX14853/MAX14855
2.75kVRMS Isolated 500kbps/25Mbps Full-Duplex
RS-485/RS-422 Transceivers with ±35kV ESD
Protection and Integrated Transformer Driver
Revision History
REVISION
NUMBER
REVISION
DATE
PAGES
CHANGED
0
3/15
Initial release
1
4/15
Updated Electrical Characteristics notes, Typical Operating Characteristics graph,
and Driver Output Protection section
2
10/15
Updated Benefits and Feature and Isolation sections and added Recommended
Transformers table
3
1/16
Corrected typos, updated Figures 1–4, and Figure 6
DESCRIPTION
—
6, 13, 17
1, 17, 18, 22
1, 8, 9, 16, 17, 19, 22
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.
Maxim Integrated cannot assume responsibility for use of any circuitry other than circuitry entirely embodied in a Maxim Integrated product. No circuit patent licenses
are implied. Maxim Integrated reserves the right to change the circuitry and specifications without notice at any time. The parametric values (min and max limits)
shown in the Electrical Characteristics table are guaranteed. Other parametric values quoted in this data sheet are provided for guidance.
Maxim Integrated and the Maxim Integrated logo are trademarks of Maxim Integrated Products, Inc.
© 2016 Maxim Integrated Products, Inc. │ 23