AD ADM3053BRWZ-REEL7 Signal and power isolated can transceiver with integrated isolated dc-to-dc converter Datasheet

Signal and Power Isolated CAN Transceiver
with Integrated Isolated DC-to-DC Converter
ADM3053
FEATURES
GENERAL DESCRIPTION
2.5 kV rms signal and power isolated CAN transceiver
isoPower integrated isolated dc-to-dc converter
5 V operation on VCC
5 V or 3.3 V operation on VIO
Complies with ISO 11898 standard
High speed data rates of up to 1 Mbps
Unpowered nodes do not disturb the bus
Connect 110 or more nodes on the bus
Slope control for reduced EMI
Thermal shutdown protection
High common-mode transient immunity: >25 kV/µs
Safety and regulatory approvals (pending)
UL recognition
2500 V rms for 1 minute per UL 1577
VDE Certificate of Conformity
DIN EN 60747-5-2 (VDE 0884 Rev.2): 2003-01
Industrial operating temperature range (−40°C to +85°C)
Available in wide-body, 20-lead SOIC package
The ADM3053 is an isolated controller area network (CAN)
physical layer transceiver with an integrated isolated dc-to-dc
converter. The ADM3053 complies with the ISO 11898 standard.
The device employs Analog Devices, Inc., iCoupler® technology
to combine a 2-channel isolator, a CAN transceiver, and
Analog Devices isoPower® dc-to-dc converter into a single
SOIC surface mount package. An on-chip oscillator outputs a pair
of square waveforms that drive an internal transformer to provide
isolated power. The device is powered by a single 5 V supply
realizing a fully isolated CAN solution.
The ADM3053 creates a fully isolated interface between the
CAN protocol controller and the physical layer bus. It is capable
of running at data rates of up to 1 Mbps.
The device has current limiting and thermal shutdown features
to protect against output short circuits. The part is fully specified
over the industrial temperature range and is available in a
20-lead, wide-body SOIC package.
The ADM3053 contains isoPower technology that uses high
frequency switching elements to transfer power through the
transformer. Special care must be taken during printed circuit
board (PCB) layout to meet emissions standards. Refer to the
AN-0971 Application Note, Control of Radiated Emissions with
isoPower Devices, for details on board layout considerations.
APPLICATIONS
CAN data buses
Industrial field networks
FUNCTIONAL BLOCK DIAGRAM
VISOOUT
VCC
isoPower DC-TO-DC CONVERTER
OSCILLATOR
RECTIFIER
REGULATOR
VIO
VISOIN
VCC
DIGITAL ISOLATION iCoupler
PROTECTION
TxD
ENCODE
TxD
RS
DECODE
RS
DECODE
RxD
ENCODE
DRIVER
SLOPE/
STANDBY
RxD
CANH
CANL
VREF
RECEIVER
REFERENCE
VOLTAGE
CAN TRANSCEIVER
ADM3053
GND2
ISOLATION
BARRIER
LOGIC SIDE
BUS SIDE
09293-001
GND1
VREF
GND2
Figure 1.
Rev. 0
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responsibility is assumed by Analog Devices for its use, nor for any infringements of patents or other
rights of third parties that may result from its use. Specifications subject to change without notice. No
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Fax: 781.461.3113
©2011 Analog Devices, Inc. All rights reserved.
ADM3053
TABLE OF CONTENTS
Features .............................................................................................. 1
Test Circuits ..................................................................................... 12
Applications ....................................................................................... 1
Circuit Description......................................................................... 13
General Description ......................................................................... 1
CAN Transceiver Operation ..................................................... 13
Functional Block Diagram .............................................................. 1
Signal Isolation ........................................................................... 13
Revision History ............................................................................... 2
Power Isolation ........................................................................... 13
Specifications..................................................................................... 3
Truth Tables................................................................................. 13
Timing Specifications .................................................................. 4
Thermal Shutdown .................................................................... 13
Switching Characteristics ............................................................ 4
DC Correctness and Magnetic Field Immunity........................... 13
Regulatory Information ............................................................... 5
Applications Information .............................................................. 15
Insulation and Safety-Related Specifications ............................ 5
PCB Layout ................................................................................. 15
VDE 0884 Insulation Characteristics (Pending) ...................... 6
EMI Considerations ................................................................... 15
Absolute Maximum Ratings............................................................ 7
Insulation Lifetime ..................................................................... 15
ESD Caution .................................................................................. 7
Typical Applications ....................................................................... 17
Pin Configuration and Function Descriptions ............................. 8
Outline Dimensions ....................................................................... 18
Typical Performance Characteristics ............................................. 9
Ordering Guide .......................................................................... 18
REVISION HISTORY
5/11—Revision 0: Initial Version
Rev. 0 | Page 2 of 20
ADM3053
SPECIFICATIONS
All voltages are relative to their respective ground; 4.5 V ≤ VCC ≤ 5.5 V; 3.0 V ≤ VIO ≤ 5.5 V. All minimum/maximum specifications apply
over the entire recommended operation range, unless otherwise noted. All typical specifications are at TA = 25°C, VCC = 5 V, VIO = 5 V
unless otherwise noted.
Table 1.
Parameter
SUPPLY CURRENT
Logic Side isoPower Current
Recessive State
Dominant State
TxD/RxD Data Rate 1 Mbps
Logic Side iCoupler Current
TxD/RxD Data Rate 1 Mbps
DRIVER
Logic Inputs
Input Voltage High
Input Voltage Low
CMOS Logic Input Currents
Differential Outputs
Recessive Bus Voltage
CANH Output Voltage
CANL Output Voltage
Differential Output Voltage
Short-Circuit Current, CANH
Symbol
Min
Typ
Max
Unit
Test Conditions
ICC
ICC
ICC
29
195
139
36
232
170
mA
mA
mA
RL = 60 Ω, RS = low, see Figure 25
RL = 60 Ω, RS = low, see Figure 25
RL = 60 Ω, RS = low, see Figure 25
IIO
1.6
2.5
mA
0.25 VIO
500
V
V
µA
Output recessive
Output dominant
TxD
200
V
V
V
V
mV
mA
mA
mA
TxD = high, RL = ∞, see Figure 22
TxD = low, see Figure 22
TxD = low, see Figure 22
TxD = low, RL = 45 Ω, see Figure 22
TxD = high, RL = ∞, see Figure 22
VCANH = −5 V
VCANH = −36 V
VCANL = 36 V
−7 V < VCANL, VCANH < +12 V, see Figure 23,
CL = 15 pF
−7 V < VCANL, VCANH < +12 V, see Figure 23,
CL = 15 pF
See Figure 3
VIH
VIL
IIH, IIL
0.7 VIO
VCANL, VCANH
VCANH
VCANL
VOD
VOD
ISCCANH
2.0
2.75
0.5
1.5
−500
3.0
4.5
2.0
3.0
+50
−200
−100
Short-Circuit Current, CANL
RECEIVER
Differential Inputs
Differential Input Voltage Recessive
ISCCANL
VIDR
−1.0
+0.5
V
Differential Input Voltage Dominant
VIDD
0.9
5.0
V
Input Voltage Hysteresis
CANH, CANL Input Resistance
Differential Input Resistance
Logic Outputs
Output Low Voltage
Output High Voltage
Short Circuit Current
VOLTAGE REFERENCE
Reference Output Voltage
COMMON-MODE TRANSIENT IMMUNITY 1
SLOPE CONTROL
Current for Slope Control Mode
Slope Control Mode Voltage
VHYS
RIN
RDIFF
5
20
25
100
mV
kΩ
kΩ
VOL
VOH
IOS
VIO − 0.3
7
1
150
0.2
VIO − 0.2
0.4
85
V
V
mA
IOUT = 1.5 mA
IOUT = −1.5 mA
VOUT = GND1 or VIO
|IREF = 50 µA|
VCM = 1 kV, transient magnitude = 800 V
VREF
2.025
25
3.025
V
kV/µs
ISLOPE
VSLOPE
−10
1.8
−200
3.3
µA
V
CM is the maximum common-mode voltage slew rate that can be sustained while maintaining specification-compliant operation. VCM is the common-mode potential
difference between the logic and bus sides. The transient magnitude is the range over which the common mode is slewed. The common-mode voltage slew rates
apply to both rising and falling common-mode voltage edges.
Rev. 0 | Page 3 of 20
ADM3053
TIMING SPECIFICATIONS
All voltages are relative to their respective ground; 3.0 V ≤ VIO ≤ 5.5 V; 4.5 V ≤ VCC ≤ 5.5 V. TA = −40°C to +85°C, unless otherwise noted.
Table 2.
Parameter
DRIVER
Maximum Data Rate
Propagation Delay from TxD On to Bus Active
Symbol
Max
Unit
tonTxD
90
Mbps
ns
Propagation Delay from TxD Off to Bus Inactive
toffTxD
120
ns
RECEIVER
Propagation Delay from TxD On to Receiver Active
tonRxD
200
630
250
480
ns
ns
ns
ns
V/µs
Typ
1
Propagation Delay from TxD Off to Receiver Inactive1
CANH, CANL SLEW RATE
1
Min
toffRxD
|SR|
7
Test Conditions
RS = 0 Ω; see Figure 2 and Figure 24
RL = 60 Ω, CL = 100 pF
RS = 0 Ω; see Figure 2 and Figure 24
RL = 60 Ω, CL = 100 pF
RS = 0 Ω; see Figure 2
RS = 47 kΩ; see Figure 2
RS = 0 Ω; see Figure 2
RS = 47 kΩ; see Figure 2
RS = 47 kΩ
Guaranteed by design and characterization.
SWITCHING CHARACTERISTICS
VIO
0.7VIO
VTxD
0.25VIO
0V
VOD
VDIFF = VCANH – VCANL
VDIFF
0.9V
0.5V
VOR
toffTxD
tonTxD
VIO
VIO – 0.3V
VRxD
0V
tonRxD
toffRxD
Figure 2. Driver Propagation Delay, Rise/Fall Timing
Rev. 0 | Page 4 of 20
09293-002
0.4V
ADM3053
VRxD
HIGH
LOW
0.9
0.5
VID (V)
09293-004
VHYS
Figure 3. Receiver Input Hysteresis
REGULATORY INFORMATION
Table 3. Pending ADM3053 Approvals
Organization
UL
VDE
Approval Type
To be recognized under the Component
Recognition Program of Underwriters
Laboratories, Inc.
To be certified according to DIN EN 60747-5-2
(VDE 0884 Rev. 2): 2003-01
Notes
In accordance with UL 1577, each ADM3053 is proof tested by applying
an insulation test voltage ≥2500 V rms for 1 second.
In accordance with VDE 0884-2.
INSULATION AND SAFETY-RELATED SPECIFICATIONS
Table 4.
Parameter
Rated Dielectric Insulation Voltage
Minimum External Air Gap (Clearance)
Minimum External Tracking (Creepage)
Minimum Internal Gap (Internal
Clearance)
Tracking Resistance (Comparative
Tracking Index)
Isolation Group
Symbol
L(I01)
Value
2500
7.7
Unit
V rms
mm
L(I02)
7.6
mm
0.017 min
mm
Conditions
1-minute duration
Measured from input terminals to output terminals,
shortest distance through air
Measured from input terminals to output terminals,
shortest distance along body
Insulation distance through insulation
>175
V
DIN IEC 112/VDE 0303-1
CTI
IIIa
Material group (DIN VDE 0110: 1989-01, Table 1)
Rev. 0 | Page 5 of 20
ADM3053
VDE 0884 INSULATION CHARACTERISTICS (PENDING)
This isolator is suitable for basic electrical isolation only within the safety limit data. Maintenance of the safety data must be ensured by
means of protective circuits.
Table 5.
Description
CLASSIFICATIONS
Installation Classification per DIN VDE 0110 for Rated
Mains Voltage
≤150 V rms
≤300 V rms
≤400 V rms
Climatic Classification
Pollution Degree
VOLTAGE
Maximum Working Insulation Voltage
Input-to-Output Test Voltage
Method b1
Highest Allowable Overvoltage
SAFETY-LIMITING VALUES
Case Temperature
Input Current
Output Current
Insulation Resistance at TS
Conditions
Symbol
VIORM
VPR
VIO = 500 V
Rev. 0 | Page 6 of 20
Unit
I to IV
I to III
I to II
40/85/21
2
DIN VDE 0110, see Table 3
VIORM × 1.875 = VPR, 100% production tested,
tm = 1 sec, partial discharge < 5 pC
(Transient overvoltage, tTR = 10 sec)
Maximum value allowed in the event of a
failure
Characteristic
424
VPEAK
795
VPEAK
VTR
4000
VPEAK
TS
IS, INPUT
IS, OUTPUT
RS
150
265
335
>109
°C
mA
mA
Ω
ADM3053
ABSOLUTE MAXIMUM RATINGS
TA = 25°C, unless otherwise noted. All voltages are relative to
their respective ground.
Table 6.
Parameter
VCC
VIO
Digital Input Voltage, TxD
Digital Output Voltage, RxD
CANH, CANL
VREF
RS
Operating Temperature Range
Storage Temperature Range
ESD (Human Body Model)
Lead Temperature
Soldering (10 sec)
Vapor Phase (60 sec)
Infrared (15 sec)
θJA Thermal Impedance
TJ Junction Temperature
Rating
−0.5 V to +6 V
−0.5 V to +6 V
−0.5 V to VIO + 0.5 V
−0.5 V to VIO + 0.5 V
−36 V to +36 V
−0.5 V to +6 V
−0.5 V to +6 V
−40°C to +85°C
−55°C to +150°C
3 kV
300°C
215°C
220°C
53°C/W
130°C
Table 7. Maximum Continuous Working Voltage1
Parameter
AC Voltage
Bipolar Waveform
Max
Unit
Reference Standard
424
V peak
50 year minimum
lifetime
Unipolar Waveform
Basic Insulation
560
V peak
Maximum approved
working voltage per
VDE 0884 Part 2
DC Voltage
Basic Insulation
560
V peak
Maximum approved
working voltage per
VDE 0884 Part 2
1
Refers to continuous voltage magnitude imposed across the isolation
barrier. See the Insulation Lifetime section for more details.
ESD CAUTION
Stresses above those listed under Absolute Maximum Ratings
may cause permanent damage to the device. This is a stress
rating only; functional operation of the device at these or any
other conditions above those indicated in the operational
section of this specification is not implied. Exposure to absolute
maximum rating conditions for extended periods may affect
device reliability.
Rev. 0 | Page 7 of 20
ADM3053
PIN CONFIGURATION AND FUNCTION DESCRIPTIONS
GND1 1
20 GND2
NC 2
19 VISOIN
GND1 3
18 RS
RxD 4
ADM3053
TxD 5
TOP VIEW
(Not to Scale)
VIO 6
GND1 7
17 CANH
16 GND2
15 CANL
14 VREF
VCC 8
GND1 9
12 VISOOUT
GND1 10
11 GND2
NOTES
1. NC = NO CONNECT. DO NOT
CONNECT TO THIS PIN.
2. PIN 12 AND PIN 19 MUST BE
CONNECTED EXTERNALLY.
09293-005
13 GND2
Figure 4. Pin Configuration
Table 8. Pin Function Descriptions
Pin No.
1
2
3
4
5
6
Mnemonic
GND1
NC
GND1
RxD
TxD
VIO
7
8
GND1
VCC
9
10
11
12
GND1
GND1
GND2
VISOOUT
13
14
15
16
17
18
19
GND2
VREF
CANL
GND2
CANH
RS
VISOIN
20
GND2
Description
Ground, Logic Side.
No Connect. Do not connect to this pin.
Ground, Logic Side.
Receiver Output Data.
Driver Input Data.
iCoupler Power Supply. It is recommended that a 0.1 μF and a 0.01 μF decoupling capacitor be fitted
between Pin 6 and GND1. See Figure 28 for layout recommendations.
Ground, Logic Side.
isoPower Power Supply. It is recommended that a 0.1 μF and a 10 μF decoupling capacitor be fitted
between Pin 8 and Pin 9.
Ground, Logic Side.
Ground, Logic Side.
Ground, Bus Side.
Isolated Power Supply Output. This pin must be connected externally to VISOIN. It is recommended that a
reservoir capacitor of 10 μF and a decoupling capacitor of 0.1 μF be fitted between Pin 12 and Pin 11.
Ground (Bus Side).
Reference Voltage Output.
Low-Level CAN Voltage Input/Output.
Ground (Bus Side).
High-Level CAN Voltage Input/Output.
Slope Resistor Input.
Isolated Power Supply Input. This pin must be connected externally to VISOOUT. It is recommended that a 0.1 μF
and a 0.01 μF decoupling capacitor be fitted between Pin 19 and Pin 20.
Ground (Bus Side).
Rev. 0 | Page 8 of 20
ADM3053
TYPICAL PERFORMANCE CHARACTERISTICS
160
180
RECEIVER INPUT HYSTERESIS (mV)
VCC = 5.5V, VIO = 5V
VCC = 5V, VIO = 5V
80
60
40
0
100
1000
DATA RATE (kbps)
165
160
VCC = 5V, VIO = 5V
155
VCC = 5V, VIO = 3.3V
150
–40
09293-100
20
170
PROPAGATION DELAY TxD ON TO BUS ACTIVE,
tonTxD (ns)
45
SLEW RATE (V/µs)
40
35
30
25
20
15
10
0
30
40
50
60
70
80
RESISTANCE, RS (Ω)
09293-101
5
20
Figure 6. Driver Slew Rate vs. Resistance, RS
60
85
53
52
51
VCC = 5V, VIO = 3.3V
50
49
VCC = 5V, VIO = 5V
48
47
–40
–15
10
35
60
85
TEMPERATURE (°C)
Figure 9. Propagation Delay from TxD On to Bus Active vs. Temperature
5.5
PROPAGATION DELAY TxD OFF TO BUS
INACTIVE, toffTxD (ns)
96
4.5
3.5
2.5
VIO = 5V
1.5
VIO = 3.3V
0.5
100
1000
DATA RATE (kbps)
Figure 7. Supply Current, IIO vs. Data Rate
94
92
VCC = 5V, VIO = 3.3V
90
88
86
VCC = 5V, VIO = 5V
84
82
80
78
–40
09293-102
SUPPLY CURRENT, IIO (mA)
35
Figure 8. Receiver Input Hysteresis vs. Temperature
50
10
10
TEMPERATURE (°C)
Figure 5. Supply Current, ICC vs. Data Rate
0
–15
09293-104
100
175
–15
10
35
TEMPERATURE (°C)
60
85
09293-105
SUPPLY CURRENT, ICC (mA)
VCC = 4.5V, VIO = 5V
120
09293-103
140
Figure 10. Propagation Delay from TxD Off to Bus Inactive vs. Temperature
Rev. 0 | Page 9 of 20
ADM3053
VCC = 5V, VIO = 3.3V, RS = 0Ω
146
144
142
140
VCC = 5V, VIO = 5V, RS = 0Ω
138
136
–15
10
35
60
85
TEMPERATURE (°C)
VCC = 5V, VIO = 5V, RS = 47kΩ
400
300
200
100
0
–40
–15
10
35
60
85
TEMPERATURE (°C)
DIFFERENTIAL OUTPUT VOLTAGE DOMINANT,
VOD (V)
200
VCC = 5V, VIO = 5V, RS = 0Ω
150
100
50
35
60
290
285
280
VCC = 5V, VIO = 5V, RS = 47kΩ
–15
10
35
60
85
2.55
2.50
2.45
VCC
VCC
VCC
VCC
2.40
= 5V,
= 5V,
= 5V,
= 5V,
VIO = 5V, RL = 60Ω
VIO = 3.3V, RL = 60Ω
VIO = 5V, RL = 45Ω
VIO = 3.3V, RL = 45Ω
2.35
2.30
–15
10
35
60
85
TEMPERATURE (°C)
85
TEMPERATURE (°C)
Figure 13. Propagation Delay from TxD Off to Receiver Inactive vs.
Temperature
2.55
VIO = 5V, TA = 25°C, RL = 60Ω
2.50
2.45
2.40
2.35
VIO = 5V, TA = 25°C, RL = 45Ω
2.30
2.25
4.5
09293-108
PROPAGATION DELAY TxD OFF TO RECEIVER
INACTIVE, toffRxD (ns)
VCC = 5V, VIO = 3.3V, RS = 0Ω
10
295
Figure 15. Differential Output Voltage Dominant vs. Temperature
250
–15
VCC = 5V, VIO = 3.3V, RS = 47kΩ
300
2.25
–40
Figure 12. Propagation Delay from TxD On to Receiver Active vs.
Temperature
0
–40
305
Figure 14. Propagation Delay from TxD Off to Receiver Inactive vs.
Temperature
DIFFERENTIAL OUTPUT VOLTAGE DOMINANT,
VOD (V)
500
310
TEMPERATURE (°C)
09293-107
PROPAGATION DELAY TxD ON TO RECEIVER
ACTIVE, tonRxD (ns)
VCC = 5V, VIO = 3.3V, RS = 47kΩ
315
275
–40
Figure 11. Propagation Delay from TxD Off to Bus Inactive vs. Temperature
600
320
4.7
4.9
5.1
5.3
5.5
SUPPLY VOLTAGE, VCC (V)
Figure 16. Differential Output Voltage Dominant vs. Supply Voltage, VCC
Rev. 0 | Page 10 of 20
09293-111
134
–40
325
09293-110
148
330
09293-109
PROPAGATION DELAY TxD OFF TO RECEIVER
INACTIVE, toffRxD (ns)
150
09293-106
PROPAGATION DELAY TxD OFF TO BUS
INACTIVE, toffTxD (ns)
152
ADM3053
2.80
VCC = 5V, VIO = 5V, IREF = +50µA
2.70
VCC = 5V, VIO =5V, IREF = +5µA
2.65
VCC = 5V, VIO = 5V, IREF = –5µA
2.60
VCC = 5V, VIO = 5V, IREF = –50µA
2.55
2.50
2.40
–40
–15
10
35
60
85
TEMPERATURE (°C)
4.885
VCC = 5V, VIO = 5V, IOUT = –1.5mA
4.880
4.875
4.870
4.865
4.860
4.855
–40
09293-112
2.45
4.890
RECEIVER OUTPUT LOW VOLTAGE, VOL (mV)
SUPPLY CURRENT, ICC (mA)
120
100
80
60
40
10
35
60
85
TEMPERATURE (°C)
09293-113
20
Figure 18. Supply Current ICC vs. Temperature
140
134
132
130
128
126
124
122
120
4.8
4.9
5.0
5.1
5.2
5.3
SUPPLY VOLTAGE, VCC (V)
5.4
5.5
09293-114
SUPPLY CURRENT, ICC (mA)
136
4.7
85
100
80
60
40
20
0
–40
–15
10
35
60
TEMPERATURE (°C)
Figure 21. Receiver Output Low Voltage vs. Temperature
VIO = 5V
TA = 25°C
DATA RATE = 1Mbps
138
4.6
60
120
VCC = 5V
VIO = 5V
140 DATA RATE = 1Mbps
RL = 60Ω
118
4.5
35
Figure 20. Receiver Output High Voltage vs. Temperature
160
–15
10
TEMPERATURE (°C)
Figure 17. Reference Voltage vs. Temperature
0
–40
–15
Figure 19. Supply Current, ICC vs. Supply Voltage VCC
Rev. 0 | Page 11 of 20
85
09293-116
REFERENCE VOLTAGE, VREF (V)
2.75
09293-115
RECEIVER OUTPUT HIGH VOLTAGE, VOH (V)
4.895
ADM3053
TEST CIRCUITS
CANH
RL
2
VOD
TxD
RL
VCANH
RL
2
CL
VOC
CANL
RxD
09293-006
VCANH
09293-008
TxD
15pF
Figure 22. Driver Voltage Measurement
Figure 24. Switching Characteristics Measurements
VID
RxD
CL
CANL
09293-007
CANH
Figure 23. Receiver Voltage Measurements
100nF
10µF
100nF
10µF
VCC
VISOOUT
isoPower DC-TO-DC CONVERTER
OSCILLATOR
RECTIFIER
REGULATOR
VIO
10µF
10µF
100nF
VCC
DIGITAL ISOLATION iCoupler
PROTECTION
TxD
ENCODE
TxD
RS
DECODE
RxD
CANH
RL
CANL
RECEIVER
REFERENCE
VOLTAGE
CAN TRANSCEIVER
ADM3053
LOGIC SIDE
RS
DRIVER
SLOPE/
STANDBY
RxD
ENCODE
VREF
GND1
RS
DECODE
VREF
GND2
ISOLATION
BARRIER
GND2
BUS SIDE
Figure 25. Supply Current Measurement Test Circuit
Rev. 0 | Page 12 of 20
09293-009
100nF
VISOIN
ADM3053
CIRCUIT DESCRIPTION
CAN TRANSCEIVER OPERATION
TRUTH TABLES
A CAN bus has two states called dominant and recessive. A
dominant state is present on the bus when the differential
voltage between CANH and CANL is greater than 0.9 V. A
recessive state is present on the bus when the differential voltage
between CANH and CANL is less than 0.5 V. During a dominant
bus state, the CANH pin is high, and the CANL pin is low.
During a recessive bus state, both the CANH and CANL pins
are in the high impedance state.
The truth tables in this section use the abbreviations found in
Table 9.
Pin 18 (RS) allows two different modes of operation to be
selected: high-speed and slope control. For high-speed
operation, the transmitter output transistors are simply
switched on and off as fast as possible. In this mode, no
measures are taken to limit the rise and fall slopes. A shielded
cable is recommended to avoid EMI problems. High-speed
mode is selected by connecting Pin 18 to ground.
Slope control mode allows the use of an unshielded twisted pair
or a parallel pair of wires as bus lines. To reduce EMI, the rise
and fall slopes should be limited. The rise and fall slopes can be
programmed with a resistor connected from Pin 18 to ground.
The slope is proportional to the current output at Pin 18.
SIGNAL ISOLATION
The ADM3053 signal isolation is implemented on the logic side of
the interface. The part achieves signal isolation by having a
digital isolation section and a transceiver section (see Figure 1).
Data applied to the TxD pin referenced to logic ground (GND1)
are coupled across an isolation barrier to appear at the transceiver
section referenced to isolated ground (GND2). Similarly, the
single-ended receiver output signal, referenced to isolated
ground in the transceiver section, is coupled across the isolation
barrier to appear at the RxD pin referenced to logic ground
(GND1). The signal isolation is powered by the VIO pin and
allows the digital interface to 3.3 V or 5 V logic.
POWER ISOLATION
The ADM3053 power isolation is implemented using an
isoPower integrated isolated dc-to-dc converter. The dc-to-dc
converter section of the ADM3053 works on principles that are
common to most modern power supplies. It is a secondary side
controller architecture with isolated pulse-width modulation
(PWM) feedback. VCC power is supplied to an oscillating circuit
that switches current into a chip-scale air core transformer.
Power transferred to the secondary side is rectified and regulated to
5 V. The secondary (VISO) side controller regulates the output by
creating a PWM control signal that is sent to the primary (VCC)
side by a dedicated iCoupler data channel. The PWM modulates
the oscillator circuit to control the power being sent to the
secondary side. Feedback allows for significantly higher power
and efficiency.
Table 9. Truth Table Abbreviations
Letter
H
L
X
Z
I
NC
Description
High level
Low level
Don’t care
High impedance (off )
Indeterminate
Not connected
Table 10. Transmitting
Supply Status
VIO
VCC
On
On
On
On
On
On
Off
On
On
Off
Input
TxD
L
H
Floating
X
L
Outputs
Bus State
CANH
Dominant
H
Recessive
Z
Recessive
Z
Recessive
Z
Indeterminate
I
CANL
L
Z
Z
Z
I
Table 11. Receiving
Supply Status
VIO
VCC
On
On
On
On
On
On
On
On
Off
On
On
Off
Inputs
VID = CANH − CANL
≥ 0.9 V
≤ 0.5 V
0.5 V < VID < 0.9 V
Inputs open
X1
X1
Bus State
Dominant
Recessive
X1
Recessive
X1
X1
Output
RxD
L
H
I
H
I
H
X = don’t care.
1
THERMAL SHUTDOWN
The ADM3053 contains thermal shutdown circuitry that protects
the part from excessive power dissipation during fault conditions.
Shorting the driver outputs to a low impedance source can
result in high driver currents. The thermal sensing circuitry
detects the increase in die temperature under this condition and
disables the driver outputs. This circuitry is designed to disable
the driver outputs when a die temperature of 150°C is reached.
As the device cools, the drivers are reenabled at a temperature of
140°C.
DC CORRECTNESS AND MAGNETIC FIELD IMMUNITY
The digital signals transmit across the isolation barrier using
iCoupler technology. This technique uses chip-scale transformer
windings to couple the digital signals magnetically from one
side of the barrier to the other. Digital inputs are encoded into
waveforms that are capable of exciting the primary transformer
Rev. 0 | Page 13 of 20
ADM3053
winding. At the secondary winding, the induced waveforms are
decoded into the binary value that was originally transmitted.
Positive and negative logic transitions at the isolator input cause
narrow (~1 ns) pulses to be sent to the decoder via the transformer.
The decoder is bistable and is, therefore, either set or reset by
the pulses, indicating input logic transitions. In the absence of
logic transitions at the input for more than 1 µs, periodic sets of
refresh pulses indicative of the correct input state are sent to
ensure dc correctness at the output. If the decoder receives no
internal pulses of more than approximately 5 μs, the input side
is assumed to be unpowered or nonfunctional, in which case,
the isolator output is forced to a default state by the watchdog
timer circuit.
This situation should occur in the ADM3053 devices only during
power-up and power-down operations. The limitation on the
ADM3053 magnetic field immunity is set by the condition in
which induced voltage in the transformer receiving coil is
sufficiently large to either falsely set or reset the decoder. The
following analysis defines the conditions under which this
can occur.
The preceding magnetic flux density values correspond
to specific current magnitudes at given distances from the
ADM3053 transformers. Figure 27 expresses these allowable
current magnitudes as a function of frequency for selected
distances. As shown in Figure 27, the ADM3053 is extremely
immune and can be affected only by extremely large currents
operated at high frequency very close to the component. For the
1 MHz example, a 0.5 kA current must be placed 5 mm away from
the ADM3053 to affect component operation.
V = (−dβ/dt)Σπrn2; n = 1, 2, … , N
where:
β is magnetic flux density (gauss).
N is the number of turns in the receiving coil.
rn is the radius of the nth turn in the receiving coil (cm).
DISTANCE = 1m
100
10
DISTANCE = 100mm
1
DISTANCE = 5mm
0.1
0.01
1k
1M
10M
100M
Figure 27. Maximum Allowable Current for Various Current-to-ADM3053
Spacings
Note that in combinations of strong magnetic field and high
frequency, any loops formed by the printed circuit board (PCB)
traces can induce error voltages sufficiently large to trigger the
thresholds of succeeding circuitry. Proceed with caution in the
layout of such traces to prevent this from occurring.
100
10
1
0.1
100M
09293-010
0.01
1M
10k
100k
10M
MAGNETIC FIELD FREQUENCY (Hz)
100k
MAGNETIC FIELD FREQUENCY (Hz)
Given the geometry of the receiving coil in the ADM3053 and
an imposed requirement that the induced voltage be, at most,
50% of the 0.5 V margin at the decoder, a maximum allowable
magnetic field is calculated as shown in Figure 26.
0.001
1k
10k
09293-011
MAXIMUM ALLOWABLE CURRENT (kA)
1k
The 3.3 V operating condition of the ADM3053 is examined
because it represents the most susceptible mode of operation.
The pulses at the transformer output have an amplitude of >1.0 V.
The decoder has a sensing threshold of about 0.5 V, thus
establishing a 0.5 V margin in which induced voltages can be
tolerated. The voltage induced across the receiving coil is
given by
MAXIMUM ALLOWABLE MAGNETIC FLUX
DENSITY (kgauss)
For example, at a magnetic field frequency of 1 MHz, the
maximum allowable magnetic field of 0.2 kgauss induces a
voltage of 0.25 V at the receiving coil. This is about 50% of the
sensing threshold and does not cause a faulty output transition.
Similarly, if such an event occurs during a transmitted pulse
(and is of the worst-case polarity), it reduces the received pulse
from >1.0 V to 0.75 V, which is still well above the 0.5 V sensing
threshold of the decoder.
Figure 26. Maximum Allowable External Magnetic Flux Density
Rev. 0 | Page 14 of 20
ADM3053
APPLICATIONS INFORMATION
PCB LAYOUT
The ADM3053 signal and power isolated CAN transceiver
contains an isoPower integrated dc-to-dc converter, requiring
no external interface circuitry for the logic interfaces. Power
supply bypassing is required at the input and output supply pins
(see Figure 28). The power supply section of the ADM3053 uses
a 180 MHz oscillator frequency to pass power efficiently through
its chip-scale transformers. In addition, the normal operation of
the data section of the iCoupler introduces switching transients
on the power supply pins.
Bypass capacitors are required for several operating frequencies.
Noise suppression requires a low inductance, high frequency
capacitor, whereas ripple suppression and proper regulation
require a large value capacitor. These capacitors are connected
between GND1 and Pin 6 (VIO) for VIO. It is recommended that
a combination of 100 nF and 10 nF be placed as shown in Figure
28 (C6 and C4. It is recommended that a combination of two
capacitors are placed between Pin 8 (VCC) and Pin 9 (GND1) for
VCC as shown in Figure 28 (C2 and C1). The VISOIN and VISOOUT
capacitors are connected between Pin 11 (GND2) and Pin 12
(VISOOUT) with recommended values of 100 nF and 10 μF as
shown in Figure 28 (C5 and C8). Two capacitors are
recommended to be fitted Pin 19 (VISOIN) and Pin 20 (GND2) with
values of 100nF and 10nF as shown in Figure 28 (C9 and C7). The
best practice recommended is to use a very low inductance
ceramic capacitor, or its equivalent, for the smaller value. The
total lead length between both ends of the capacitor and the
input power supply pin should not exceed 10 mm.
pins exceeding the absolute maximum ratings for the device,
thereby leading to latch-up and/or permanent damage.
The ADM3053 dissipates approximately 650 mW of power
when fully loaded. Because it is not possible to apply a heat sink
to an isolation device, the devices primarily depend on heat
dissipation into the PCB through the GND pins. If the devices
are used at high ambient temperatures, provide a thermal path
from the GND pins to the PCB ground plane. The board layout
in Figure 28 shows enlarged pads for Pin 1, Pin 3, Pin 9, Pin 10,
Pin 11, Pin 14, Pin 16, and Pin 20. Implement multiple vias from
the pad to the ground plane to reduce the temperature inside the
chip significantly. The dimensions of the expanded pads are at
the discretion of the designer and dependent on the available
board space.
EMI CONSIDERATIONS
The dc-to-dc converter section of the ADM3053 must, of
necessity, operate at very high frequency to allow efficient
power transfer through the small transformers. This creates
high frequency currents that can propagate in circuit board
ground and power planes, causing edge and dipole radiation.
Grounded enclosures are recommended for applications that
use these devices. If grounded enclosures are not possible, good
RF design practices should be followed in the layout of the PCB.
See the AN-0971 Application Note, Control of Radiated Emissions
with isoPower Devices, for more information.
INSULATION LIFETIME
All insulation structures eventually break down when subjected to
voltage stress over a sufficiently long period. The rate of insulation
degradation is dependent on the characteristics of the voltage
waveform applied across the insulation. Analog Devices conducts
an extensive set of evaluations to determine the lifetime of the
insulation structure within the ADM3053.
09293-012
Accelerated life testing is performed using voltage levels higher
than the rated continuous working voltage. Acceleration factors for
several operating conditions are determined, allowing calculation
of the time to failure at the working voltage of interest. The values
shown in Table 5 summarize the peak voltages for 50 years of
service life in several operating conditions. In many cases, the
working voltage approved by agency testing is higher than the 50
year service life voltage. Operation at working voltages higher than
the service life voltage listed leads to premature insulation
failure.
Figure 28. Recommended PCB Layout
In applications involving high common-mode transients, ensure
that board coupling across the isolation barrier is minimized.
Furthermore, design the board layout such that any coupling
that does occur equally affects all pins on a given component
side. Failure to ensure this can cause voltage differentials between
The insulation lifetime of the ADM3053 depends on the voltage
waveform type imposed across the isolation barrier. The iCoupler
insulation structure degrades at different rates, depending on
whether the waveform is bipolar ac, unipolar ac, or dc. Figure 29,
Figure 30, and Figure 31 illustrate these different isolation voltage
waveforms.
Rev. 0 | Page 15 of 20
ADM3053
Bipolar ac voltage is the most stringent environment. A 50 year
operating lifetime under the bipolar ac condition determines
the Analog Devices recommended maximum working voltage.
0V
NOTES
1. THE VOLTAGE IS SHOWN AS SINUSODIAL FOR ILLUSTRATION
PURPOSES ONLY. IT IS MEANT TO REPRESENT ANY VOLTAGE
WAVEFORM VARYING BETWEEN 0 AND SOME LIMITING VALUE.
THE LIMITING VALUE CAN BE POSITIVE OR NEGATIVE, BUT THE
VOLTAGE CANNOT CROSS 0V.
09293-013
RATED PEAK VOLTAGE
0V
Figure 29. Bipolar AC Waveform
09293-014
RATED PEAK VOLTAGE
0V
Figure 30. DC Waveform
Rev. 0 | Page 16 of 20
Figure 31. Unipolar AC Waveform
09293-015
In the case of unipolar ac or dc voltage, the stress on the insulation
is significantly lower. This allows operation at higher working
voltages while still achieving a 50 year service life. The working
voltages listed in Table 5 can be applied while maintaining the
50 year minimum lifetime, provided the voltage conforms to either
the unipolar ac or dc voltage cases. Any cross insulation voltage
waveform that does not conform to Figure 30 or Figure 31 should
be treated as a bipolar ac waveform, and its peak voltage should
be limited to the 50-year lifetime voltage value listed in Table 5.
RATED PEAK VOLTAGE
ADM3053
TYPICAL APPLICATIONS
Figure 32 is an example circuit diagram using the ADM3053.
5V
SUPPLY
100nF
10µF
100nF
10µF
VISOOUT
VCC
isoPowerDC-TO-DC CONVERTER
OSCILLATOR
RECTIFIER
3.3V/5V
SUPPLY
REGULATOR
VIO
10nF
VISOIN
100nF
100nF
10nF
VCC
DIGITAL ISOLATION iCoupler
ENCODE
DECODE
ENCODE
RT
CANL
RECEIVER
REFERENCE
VOLTAGE
CAN TRANSCEIVER
ADM3053
LOGIC SIDE
CANH
CANH
RxD
VREF
GND1
RS
DRIVER
SLOPE/
STANDBY
VREF
CANL
BUS
CONNECTOR
GND2
ISOLATION
BARRIER
GND2
BUS SIDE
Figure 32. Example Circuit Diagram Using the ADM3053
Rev. 0 | Page 17 of 20
09293-016
RxD
RS
DECODE
RS
CAN
CONTROLLER
PROTECTION
TxD
TxD
ADM3053
OUTLINE DIMENSIONS
13.00 (0.5118)
12.60 (0.4961)
11
20
7.60 (0.2992)
7.40 (0.2913)
10
2.65 (0.1043)
2.35 (0.0925)
0.30 (0.0118)
0.10 (0.0039)
COPLANARITY
0.10
10.65 (0.4193)
10.00 (0.3937)
1.27
(0.0500)
BSC
0.51 (0.0201)
0.31 (0.0122)
SEATING
PLANE
0.75 (0.0295)
45°
0.25 (0.0098)
8°
0°
0.33 (0.0130)
0.20 (0.0079)
COMPLIANT TO JEDEC STANDARDS MS-013-AC
CONTROLLING DIMENSIONS ARE IN MILLIMETERS; INCH DIMENSIONS
(IN PARENTHESES) ARE ROUNDED-OFF MILLIMETER EQUIVALENTS FOR
REFERENCE ONLY AND ARE NOT APPROPRIATE FOR USE IN DESIGN.
1.27 (0.0500)
0.40 (0.0157)
06-07-2006-A
1
Figure 33. 20-Lead Standard Small Outline Package [SOIC_W]
Wide Body
(RW-20)
Dimensions shown in millimeters and (inches)
ORDERING GUIDE
Model1
ADM3053BRWZ
ADM3053BRWZ-REEL7
EVAL-ADM3053EBZ
1
Temperature Range
−40°C to +85°C
−40°C to +85°C
Package Description
20-Lead SOIC_W
20-Lead SOIC_W
ADM3053 Evaluation Board
Z = RoHS Compliant Part.
Rev. 0 | Page 18 of 20
Package Option
RW-20
RW-20
ADM3053
NOTES
Rev. 0 | Page 19 of 20
ADM3053
NOTES
©2011 Analog Devices, Inc. All rights reserved. Trademarks and
registered trademarks are the property of their respective owners.
D09293-0-5/11(0)
Rev. 0 | Page 20 of 20
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