Datasheet ADM3052 Datasheet (ANALOG DEVICES)

Isolated CAN Transceiver with Integrated

V

High Voltage, Bus-Side, Linear Regulator

FEATURES

5 kV rms isolated CAN transceiver Integrated V Bus side powered by V 11 V to 25 V operation on V 5 V or 3.3 V operation on V Complies with ISO 11898 standard High speed data rates up to 1 Mbps Short-circuit protection on bus pins Integrated bus miswire protection Unpowered nodes do not disturb the bus 110 or more nodes on the bus Thermal shutdown protection High common-mode transient immunity: >25 kV/μs Safety and regulatory approvals

UL recognition (pending)

5000 V

VDE Certificates of Conformity (pending)

DIN V VDE V 0884-10 (VDE V 0884-10):2006-12

V Industrial operating temperature range: −40°C to +85°C Wide body, 16-lead SOIC package

linear regulator

+

for 1 minute per UL 1577

RMS

= 846 V peak

IORM

and V

+

DD1

−

ADM3052

GENERAL DESCRIPTION

The ADM3052 is an isolated controller area network (CAN) physical layer transceiver with a V The ADM3052 complies with the ISO 11898 standard.

The device employs Analog Devices, Inc., iCoupler® technology to combine a 3-channel isolator, a CAN transceiver, and a linear regulator into a single package. The power is isolated between a single 3.3 V or 5 V supply on V 24 V supply provided on V

+

The ADM3052 creates an isolated interface between the CAN protocol controller and the physical layer bus. It is capable of running at data rates up to 1 Mbps.

The device has integrated miswire protection on the bus pins, V

, V−, CANH, and CANL.

+

The device has current-limiting and thermal shutdown features to protect against output short circuits and situations where the bus may be shorted to ground or power terminals. The part is fully specified over the industrial temperature range and is available in a 16-lead, wide-body SOIC package.

integrated linear regulator.

+

, the logic side, and a single

DD1

, the bus side.

APPLICATIONS

CAN data buses Industrial field networks DeviceNet applications

FUNCTIONAL BLOCK DIAGRAM

DD1

ISOLATION

BARRIER

V

DD2

V

+SENSE

TxD

RxD

Rev. 0

Information furnished by Analog Devices is believed to be accurate and reliable. However, no 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 license is granted by implication or otherwise under any patent or patent rights of Analog Devices. Trademarks and registered trademarks are the property of their respective owners.

DECODE ENCODE

ENCODE

DECODE

DIGITAL ISOLATION

GND

1

LOGIC SIDE

DECODE

ENCODE

GND

ADM3052

2

C

INT

LINEAR

REGULATOR

BUS

V

+SENSE

TxD

RxD

V

REF

BUS SIDE

RECEIVER

REFERENCE

VOLTAGE

CAN TRANSCEI V E R

PROTECTION

DRIVER

GND

V

DD2

2

V

+R

V

+

CANH CANL

V

REF

V

–

Figure 1.

09292-001

ADM3052

REVISION HISTORY

6/11—Revision 0: Initial Version

Rev. 0 | Page 2 of 20

ADM3052

SPECIFICATIONS

All voltages are relative to their respective ground; 3.0 V ≤ V

Table 1.

Parameter Symbol Min Typ Max Unit Test Conditions

SUPPLY CURRENT

Power Supply Current Logic Side

TxD/RxD Data Rate 1 Mbps I

0.7 2 mA

DD1

Power Supply Current Bus Side

Recessive State I+ 10 mA RL = 60 Ω, see Figure 26

Dominant State I+ 64 75 mA RL = 60 Ω, see Figure 26

TxD/RxD Data Rate 1 Mbps I+ 48 55 mA RL = 60 Ω, see Figure 26

EXTERNAL RESISTOR

Resistance RP 297 300 303 Ω Power Rating 0.75 W

DRIVER

Logic Inputs

Input Voltage High VIH 0.7 V

Input Voltage Low VIL 0.25 V

CMOS Logic Input Currents IIH, IIL 500 μA TxD

Differential Outputs

Recessive Bus Voltage V

CANH Output Voltage V

CANL Output Voltage V

, V

CANL

CANH

0.5 2.0 V V

CANL

2.0 3.0 V V

CANH

2.75 4.5 V V

Differential Output Voltage VOD 1.5 3.0 V V

V

Short-Circuit Current, CANH I

−500 +50 mV V

OD

−200 mA V

SCCANH

−100 mA V Short-Circuit Current, CANL I

200 mA V

SCCANL

RECEIVER

Differential Inputs

Voltage Recessive V

Voltage Dominant V

Input Voltage Hysteresis V

−1.0 +0.5 V

IDR

0.9 5.0 V

IDD

150 mV See Figure 24

HYS

CANH, CANL Input Resistance RIN 5 25 kΩ

Differential Input Resistance R

20 100 kΩ

DIFF

Logic Outputs

Output Low Voltage VOL 0.2 0.4 V I

Output High Voltage VOH V

Short-Circuit Current IOS 7 85 mA V

VOLTAGE REFERENCE

Reference Output Voltage V

2.025 3.025 V |I

REF

BUS VOLTAGE SENSE

V

Output Voltage Low VOL 0.2 0.4 V I

+SENSE

V

Output Voltage High VOH V

+SENSE

Threshold Voltage V

COMMON-MODE TRANSIENT

IMMUNITY

1

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.

1

7.0 10 V

+SENSETH

25 kV/μs V

≤ 5.5 V, TA = −40°C to +85°C, V+ = 11 V to 25 V, unless otherwise noted.

DD1

V TxD

DD1

V TxD

DD1

= high, RL = ∞, see Figure 23

TxD

= low, see Figure 23

TxD

= low, see Figure 23

TxD

= low, RL = 45 Ω, see Figure 23

TxD

= high, RL = ∞, see Figure 23

TxD

= −5 V

CANH

= −36 V

CANH

= 36 V

CANL

, V

< 12 V, see Figure 24,

CANH

, V

< 12 V, see Figure 24,

CANH

DD1

− 0.3 V

DD1

− 0.3 V

DD1

− 0.2 V I

DD1

− 0.2 V I

DD1

−7 V < V C

CANL

= 15 pF

L

CANL

= 15 pF

L

= 1.5 mA

OUT

= −1.5 mA

OUT

= GND1 or V

OUT

= 50 μA|

REF

= 1.5 mA

O+SENSE

= −1.5 mA

O+SENSE

= 1 kV, transient magnitude = 800 V

CM

Rev. 0 | Page 3 of 20

ADM3052

TIMING SPECIFICATIONS

All voltages are relative to their respective ground; 3.0 V ≤ V

Table 2.

Parameter Symbol Min Typ Max Unit Test Conditions

DRIVER

Maximum Data Rate 1 Mbps Propagation Delay from TxD On to Bus Active t

Propagation Delay from TxD Off to Bus Inactive t

RECEIVER

Propagation Delay from TxD On to Receiver Active t

Propagation Delay from TxD Off to Receiver Inactive t

POWER-UP

Enable Time, V+ High to V Disable Time, V+ Low to V

Low tSE 300 μs See Figure 29

+SENSE

High tSD 10 ms See Figure 29

+SENSE

REGULATORY INFORMATION

The ADM3052 approval is pending by the organizations listed in Table 3.

≤ 5.5 V, TA = −40°C to +85°C, V+ = 11 V to 25 V, unless otherwise noted.

DD1

90 ns

onTxD

See Figure 25 and Figure 27, RL = 60 Ω, CL = 100 pF

120 ns

offTxD

200 ns

onRxD

250 ns

offRxD

See Figure 25 and Figure 27,

= 60 Ω, CL = 100 pF

R

L

See Figure 25 and Figure 27,

= 60 Ω, CL = 100 pF

R

L

See Figure 25 and Figure 27,

= 60 Ω, CL = 100 pF

R

L

Table 3.

Organization Approval Type Notes

UL

Recognized under the component recognition program of Underwriters Laboratories, Inc.

In accordance with UL 1577, each ADM3052 is proof tested by applying an insulation test voltage ≥6000 V rms for 1 second (current leakage detection limit = 10 μA)

VDE

Certified according to DIN V VDE V 0884-10 (VDE V 0884-10):2006-12

In accordance with DIN V VDE V 0884-10, each ADM3052 is proof tested by applying an insulation test voltage ≥1590 V peak for 1 second (partial discharge detection limit = 5 pC)

INSULATION AND SAFETY-RELATED SPECIFICATIONS

Table 4.

Parameter Symbol Value Unit Conditions

Rated Dielectric Insulation Voltage 5000 V rms 1-minute duration Minimum External Air Gap (Clearance) L(I01) 7.7 mm

Minimum External Tracking (Creepage) L(I02) 7.6 mm

Minimum Internal Gap (Internal Clearance) 0.017 min mm Insulation distance through insulation Tracking Resistance (Comparative Tracking Index) CTI >175 V DIN IEC 112/VDE 0303-1 Isolation Group IIIa Material group (DIN VDE 0110)

Measured from input terminals to output terminals, shortest distance through air

Measured from input terminals to output terminals, shortest distance along body

Rev. 0 | Page 4 of 20

ADM3052

VDE 0884 INSULATION CHARACTERISTICS (PENDING)

This isolator is suitable for reinforced electrical isolation within the safety limit data. Maintenance of the safety data must be ensured by means of protective circuits.

Table 5.

Description Test Conditions Symbol Characteristic Unit

CLASSIFICATIONS

Installation Classification per DIN VDE 0110 for Rated

Mains Voltage

≤150 V rms I to IV ≤300 V rms I to III

≤400 V rms I to II Climatic Classification 40/85/21 Pollution Degree DIN VDE 0110 2

VOLTAGE

Maximum Working Insulation Voltage V Input-to-Output Test Voltage, Method B1

× 1.875 = VPR, 100% production tested,

V

IORM

= 1 sec, partial discharge < 5 pC

t

m

Input-to-Output Test Voltage, Method A VPR 1357 V peak

After Environmental Tests, Subgroup 1

× 1.6 = VPR, tm = 60 sec,

V

IORM

partial discharge < 5 pC

After Input and/or Safety Test,

Subgroup 2/Subgroup 3

V

× 1.2 = VPR, tm = 60 sec,

IORM

partial discharge < 5 pC

Highest Allowable Overvoltage VTR 6000 V peak

SAFETY-LIMITING VALUES

Case Temperature TS 150 °C Input Current I Output Current I Insulation Resistance at TS R

846 V peak

IORM

1590 V peak

V

PR

1018 V peak

265 mA

S, INPUT

335 mA

S, OUTPUT

>109 Ω

S

Rev. 0 | Page 5 of 20

ADM3052

ABSOLUTE MAXIMUM RATINGS

TA = 25°C, unless otherwise noted. All voltages are relative to their respective ground.

Table 6.

Parameter Rating V

−0.5 V to +6 V

DD1

V+ −36 V to +36 V V+R −36 V to +36 V Digital Input Voltage

TxD −0.5 V to V

Digital Output Voltage

RxD −0.5 V to V V

−0.5 V to V

+SENSE

CANH, CANL −36 V to +36 V V

−0.5 V to +6 V

REF

Operating Temperature Range −40°C to +85°C Storage Temperature Range −55°C to +150°C ESD (Human Body Model)

3 kV

Lead Temperature

Soldering (10 sec) 300°C Vapor Phase (60 sec) 215°C

Infrared (15 sec) 220°C θJA, Thermal Impedance 53°C/W TJ, Junction Temperature 130°C

+ 0.5 V

DD1

+ 0.5 V

DD1

+ 0.5 V

DD1

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.

ESD CAUTION

Rev. 0 | Page 6 of 20

ADM3052

V

PIN CONFIGURATION AND FUNCTION DESCRIPTIONS

NC

1

GND

2

1

3

GND

1

ADM3052

4

+SENSE

RxD

TxD

V

DD1

GND

NOTES

1. NC = NO CONNECT. DO NOT CONNECT TO THIS PI N.

5 6 7 8

1

TOP VIEW

(Not to Scale)

Figure 2. Pin Configuration

Table 7. Pin Function Descriptions

Pin No. Mnemonic Description

1 NC No Connect. Do not connect to this pin. 2 GND1 Ground (Logic Side). 3 GND1 Ground (Logic Side). 4 V

+SENSE

Bus Voltage Sense. A low level on V A high level on V

indicates that power is not connected on the bus on V+ and V−.

+SENSE

5 RxD Receiver Output Data. 6 TxD Driver Input Data. 7 V

DD1

Power Supply (Logic Side). Decoupling capacitor to GND1 required; capacitor value should be between

0.01 μF and 0.1 μF. 8 GND1 Ground (Logic Side). 9 V− Ground (Bus Side). 10 V

Reference Voltage Output.

REF

11 CANL Low Level CAN Voltage Input/Output. 12 CANH High Level CAN Voltage Input/Output. 13 C

INT

14 V+R

A capacitor of 1 μF, 10 V is required on this pin. Connect a 300 Ω, 750 mW resistor between V

between V

and GND2.

+R

15 V+ Bus Power Connection. Connect a 300 Ω, 750 mW resistor between V+R and V+. 16 V− Ground (Bus Side).

16

V

–

15

V

+

14

V

+R

13

C

INT

12

CANH

11

CANL

10

V

REF

9

V

–

09292-006

indicates that there is power connected on the bus on V+ and V−.

+SENSE

and V+. It is recommended that a 10 μF capacitor be fitted

+R

Rev. 0 | Page 7 of 20

ADM3052

TYPICAL PERFORMANCE CHARACTERISTICS

164

V

= 3.3V, V + = 25V

DD1

V

= 5V, V+ = 25V

DD1

162

160

(ns)

158

onRxD

t

156

154

152

RECEIVER ACTIVE,

PROPAGATION DELAY TxD ON TO

150

195

194

(ns)

193

offRxD

t

192

191

190

RECEIVER INACTIVE,

PROPAGATION DELAY TxD OFF TO

189

V

= 3.3V, TA = 25°C

DD1

V

= 5V, TA = 25°C

DD1

148

–40 –15 10 35 60 85

TEMPERATURE (°C)

Figure 3. Propagation Delay from TxD On to Receiver Active

vs. Temperature

157

156

(ns)

155

onRxD

t

154

153

RECEIVER ACTIVE,

PROPAGATION DELAY TxD ON TO

152

151

11 13 15 17 19 21 23 25

SUPPLY VOLTAGE, V+ (V)

V

= 3.3V, TA = 25°C

DD1

V

= 5V, TA = 25°C

DD1

Figure 4. Propagation Delay from TxD On to Receiver Active

vs. Supply Voltage, V

250

V

= 3.3V, V+ = 25V

DD1

V

= 5V, V+ = 25V

DD1

200

(ns)

offRxD

t

150

100

50

RECEIVER INACTIVE,

PROPAGATION DELAY TxD OFF TO

0

–40 –15 10 35

TEMPERATURE (°C)

+

60 85

Figure 5. Propagation Delay from TxD Off to Receiver Inactive

vs. Temperature

188

11 13 15 17 19 252321

09292-023

SUPPLY VOLTAGE, V+ (V)

09292-026

Figure 6. Propagation Delay from TxD Off to Receiver Inactive

vs. Supply Voltage, V

90

V+ = 25V

85

(ns)

offTxD

80

t

75

70

65

PROPAGATI ON DELAY,

60

–40 –15 10 35 60 85

09292-024

V

= 3.3V

DD1

V

= 5V

DD1

TEMPERATURE (°C)

+

09292-015

Figure 7. Propagation Delay from TxD Off to Bus Inactive vs. Temperature

85

V

= 3.3V, TA = 25°C

DD1

V

= 5V, TA = 25°C

DD1

84

83

82

(ns)

81

offTxD

t

80

79

78

BUS INACTIVE,

77

PROPAGATION DELAY TxD OFF TO

76

75

11 13 15 17 19 21 23 25

09292-025

SUPPLY VOLTAGE, V+ (V)

09292-029

Figure 8. Propagation Delay from TxD Off to Bus Inactive

vs. Supply Voltage, V

+

Rev. 0 | Page 8 of 20

ADM3052

51

V

= 3.3V, V+ = 25V

DD1

V

= 5V, V+ = 25V

DD1

50

49

(ns)

48

onTxD

t

47

46

BUS ACTIVE,

PROPAGATION DELAY TxD ON TO

45

44

–40 –15 10 35 60 85

TEMPERATURE (°C)

Figure 9. Propagation Delay from TxD On to Bus Active vs. Temperature

51

V

= 3.3V, TA = 25°C

DD1

V

= 5V, TA = 25°C

DD1

50

49

(ns)

onTxD

48

47

46

TO BUS ACTIVE, t

PROPAGATION DELAY TxD ON

45

44

11 13 15 17 19 21 23 25

SUPPLY VOLTAGE, V+ (V)

Figure 10. Propagation Delay from TxD On to Bus Active

vs. Supply Voltage, V

+

51

V

= 3.3V, V + = 25V

DD1

V

= 5V, V+ = 25V

DD1

50

49

(ns)

onTxD

48

47

46

TO BUS ACTIVE, t

PROPAGATION DELAY TxD ON

45

44

–40 –15 10 35 60 85

09292-023

TEMPERATURE (°C)

09292-021

Figure 12. Propagation Delay from TxD On to Bus Active vs. Temperature

50

V+ = 11V, V V+ = 18V, V

48

V+ = 25V, V

46

44

42

40

38

36

SUPPLY CURRENT, I+ (mA)

34

32

30

100 1000

09292-022

Figure 13. Supply Current (I+) vs. Data Rate (Across V+, V

= 5V, TA = 25°C

DD1

= 5V, TA = 25°C

DD1

= 5V, TA = 25°C

DD1

DATA RATE (kbps)

DD1

09292-019

= 5 V)

2.40

V

= 3.3V, TA = 25°C

DD1

= 5V, TA = 25°C

V

DD1

2.39

2.38

2.37

(V)

2.36

OD

V

2.35

2.34

2.33

DIFFERENT IAL OUTPUT VOLTAGE DOMINANT,

2.32

11 13 15 17 19 21 23 25

SUPPLY VOLTAGE, V+ (V)

Figure 11. Differential Output Voltage Dominant vs. Supply Voltage, V+

09292-028

Rev. 0 | Page 9 of 20

1.2

1.0

(mA)

0.8

DD1

0.6

0.4

SUPPLY CURRENT, I

0.2

Figure 14. Supply Current (I

= 3.3V, V+ = 24V , TA = 25°C

V

DD1

V

= 5V, V+ = 24V, TA = 25°C

DD1

0

100 1000

DATA RATE (kbps)

) vs. Data Rate (V

DD1

= 3.3 V, 5 V; V+ = 24 V)

DD1

09292-020

ADM3052

A

T

2.42 V

= 3.3V, V + = 25V

DD1

= 5V, V+ = 25V

V

DD1

2.40

2.38

AGE DOMINANT,

2.36

(V)

2.34

OD

V

2.32

L OUTPUT VOL

2.30

2.28

DIFFERENTI

2.26

–40 –15 10 35 60 85

TEMPERATURE (°C)

Figure 15. Driver Differential Output Voltage Dominant vs. Temperature

120

(mV)

100

OL

80

60

40

20

RECEIVER OUT P UT LOW VOLTAGE, V

0

–40 –15 10 35 60 85

09292-027

TEMPERATURE (°C)

09292-030

Figure 18. Receiver Output Low Voltage vs. Temperature

2.40 V

= 3.3V, TA = 25°C

DD1

= 5V, TA = 25°C

V

DD1

2.39

2.38

2.37

(V)

2.36

OD

V

2.35

2.34

2.33

DIFFERENT IAL OUTPUT VOLTAGE DOMINANT,

2.32

11 13 15 17 19 21 23 25

SUPPLY VOLTAGE, V+ (V)

Figure 16. Driver Differential Output Voltage Dominant vs. Supply Voltage, V+

4.895

(V)

4.890

OH

4.885

4.880

4.875

4.870

4.865

4.860

RECEIVER OUTPUT HIGH VOLTAGE, V

4.855

–40 –15 10 35 60 85

TEMPERATURE (°C)TEMPERATURE (°C)

VCC = 5V

= –1.5mA

I

OUT

09292-031

Figure 17. Receiver Output High Voltage vs. Temperature

2.80

2.75

(V)

2.70

REF

VCC = 5V, I

= 5V, I

V

CC

= 5V, I

V

CC

= 5V, I

V

CC

REF REF REF REF

= +50µA = –50µA = +5µA = –5µA

2.65

2.60

2.55

2.50

REFERENCE VOLTAGE, V

2.45

2.40

–40

09292-033

–15 1 0

TEMPERATURE (°C)

Figure 19. V

35 60 85

vs. Temperature

REF

09292-032

85

80

(µs)

SE

t

75

70

ENABLE TIME ,

+SENSE

65

V

60

Figure 20. Enable Time, V+ High to V

V

= 3.3V

DD1

= 5V

V

DD1

–40 –15 10 35 60 85

TEMPERATURE (°C)

Low vs. Temperature

+SENSE

09292-016

Rev. 0 | Page 10 of 20

ADM3052

680

670

660

(µs)

SD

t

650

640

DISABLE,

630

+SENSE

620

V

610

600

–40 –15 10 35 60 85

Figure 21. Disable Time, V+ Low to V

V

= 3.3V

DD1

TEMPERATURE (°C)

+SENSE

= 5V

V

DD1

High vs. Temperature

8.56

V

= 3.3V

DD1

V

= 5V

DD1

8.54

8.52

8.50

8.48

8.46

8.44

THRESHOLD VOLTAGE HIGH TO LOW (V)

8.42

+SENSE

V

8.40

–40 –15 10 35 60 85

09292-017

TEMPERATURE (°C)

09292-018

Figure 22. Bus Voltage Sense Threshold Voltage High to Low vs. Temperature

Rev. 0 | Page 11 of 20

ADM3052

T

C

TEST CIRCUITS

CANH

V

+SENSE

TxD

R

V

CANL

L

2

R

L

2

xD

V

OD

CANH

Figure 23. Driver Voltage Measurements

ANH

V

ID

CANL

C

L

Figure 24. Receiver Voltage Measurements

V

DD1

ISOLATION

BARRIER

DECODE ENCODE

ENCODE

V

OC

RxD

DECODE

TxD

CANL

RxD

09292-007

15pF

R

C

L

09292-009

Figure 25. Switching Characteristics Measurements

09292-008

1µF

C

INT

V

LINEAR

REGULATOR

V

DD2

BUS

V

TxD

+SENSE

PROTECTION

DRIVER

V

DD2

+R

R

P

V

+

10µF

100nF

CANH CANL

V

REF

V

–

R

L

09292-010

RxD

DECODE

DIGITAL ISOLATION

GND

1

LOGIC SIDE

ENCODE

GND

ADM3052

RxD

V

REF

2

RECEIVER

REFERENCE

VOLTAGE

CAN TRANSCEIVER

GND

2

BUS SIDE

Figure 26. Supply Current Measurement Test Circuit

Rev. 0 | Page 12 of 20

ADM3052

V

SWITCHING CHARACTERISTICS

DD1

V

TxD

0V

V

OD

V

DIFF

V

OR

V

DD1

V

RxD

0V

0.25V

0.9V

t

onTxD

t

onRxD

DD1

V

= V

DIFF

0.4V

Figure 27. Driver and Receiver Propagation Delay

CANH

– V

0.7V

CANL

DD1

t

offTxD

t

offRxD

0.5V

V

– 0.3V

DD1

09292-002

V

RxD

HIGH

0.5

V

HYS

0.9

VID (V)

LOW

09292-004

Figure 28. Receiver Input Hysteresis

25

V

+SENSETH

t

SD

– 0.3

V

DD1

09292-005

+SENSE

V

+

0V

V

DD1

0V

V

+SENSETH

t

SE

Figure 29. V

0.4V

Enable/Disable Time

+SENSE

Rev. 0 | Page 13 of 20

ADM3052

CIRCUIT DESCRIPTION

CAN TRANSCEIVER OPERATION

A CAN bus has two states: 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.

ELECTRICAL ISOLATION

In the ADM3052, electrical isolation is implemented on the logic side of the interface. Therefore, the part has two main sections: a digital isolation section and a transceiver section (see Figure 30). The driver input signal, which is applied to the TxD pin and referenced to the logic ground (GND across an isolation barrier to appear at the transceiver section referenced to the isolated ground (V input and V the tr to a

ppear at the RxD pin and V

, which are referenced to the isolated ground in

+

ansceiver section, are coupled across the isolation barrier

). Similarly, the receiver

−

referenced to the logic

+SENSE

ground, respectively.

iCoupler Technology

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 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 input cause narrow (~1 ns) pulses to be sent to the decoder via the transformer. The decoder is bistable and is, therefore, set or reset by the pulses, indicating input logic transitions. In the absence of logic transitions at the input for more than ~1 μs, a periodic set of refresh pulses, indicative of the correct input state, is sent to ensure dc correctness at the output. If the decoder receives no internal pulses for more than about 5 μs, the input side is assumed to be unpowered or nonfunctional, in which case the output is forced to a default state (see Ta ble 9 and Tabl e 10 ).

), is coupled

1

TRUTH TABLES

The truth tables in this section use the abbreviations shown in Tab l e 8.

Table 8. Truth Table Abbreviations

Letter Description

H High level L Low level I Indeterminate X Don’t care Z High impedance (off) NC Disconnected

Table 9. Transmitting

Supply Status Input Outputs

V

V+ TxD Bus State CANH CANL V

DD1

On On L Dominant H L L On On H Recessive Z Z L On On Floating Recessive Z Z L Off On X Recessive Z Z I On Off L I I I H

Table 10. Receiving

Supply Status Inputs Outputs

V

V+ VID = CANH − CANL Bus State RxD V

DD1

On On On On ≤ 0.5 V Recessive H L On On 0.5 V < VID < 0.9 V I I L On On Inputs open Recessive H L Off On X X I I On Off X X H H

≥ 0.9 V

Dominant L L

+SENSE

Rev. 0 | Page 14 of 20

ADM3052

1µF

V

+SENSE

TxD

V

DD1

ISOLATION

BARRIER

DECODE ENCODE

ENCODE

V

DD2

DECODE

C

INT

LINEAR

REGULATOR

BUS

V

+SENSE

TxD

PROTECTION

DRIVER

V

+R

R

P

V

DD2

+

10µF

100nF

RxD

DECODE

DIGITAL ISOLATION

GND

1

LOGIC SIDE

RxD

ENCODE

GND

ADM3052

V

REF

2

RECEIVER

REFERENCE

VOLTAGE

CAN TRANSCEIVER

BUS SIDE

Figure 30. Digital Isolation and Transceiver Sections

GND

CANH

R

CANL

V

2

V

–

REF

L

09292-010

Rev. 0 | Page 15 of 20

ADM3052

THERMAL SHUTDOWN

The ADM3052 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 junction temperature of 150°C is reached. As the device cools, the drivers reenable at a temperature of 140°C.

LINEAR REGULATOR

The linear regulator takes the V+ bus power (ranging between 11 V to 25 V) and regulates this voltage to 5 V to provide power to the internal bus-side circuitry (iCoupler isolation, V

+SENSE

, and transceiver circuits). The linear regulator uses two regulation loops to share the power dissipation between the internal die and an external resistor. This reduces the internal heat dissipation in the package. The 300 Ω external resistor should be capable of dissipating 750 mW of power and have a tolerance of 1%.

MAGNETIC FIELD IMMUNITY

The limitation on the magnetic field immunity of the iCoupler is set by the condition in which an induced voltage in the receiving coil of the transformer is large enough to either falsely set or reset the decoder. The following analysis defines the conditions under which this may occur. The 3 V operating condition of the

ADM3052 is examined because it represents the most susceptible

mode of operation.

The pulses at the transformer output have an amplitude greater than 1 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

d

β−

⎞

⎛

V

=

⎜

dt

⎝

where:

β is the magnetic flux density (gauss). N is the number of turns in the receiving coil.

is the radius of the nth turn in the receiving coil (cm).

r

n

Given the geometry of the receiving coil and an imposed requirement that the induced voltage is, at most, 50% of the

0.5 V margin at the decoder, a maximum allowable magnetic field can be determined using Figure 31.

2

; Nn ,...,2,1=

π

r

⎟

∑

n

⎠

100

10

1

0.1

FLUX DENSITY (kGAUSS)

0.01

MAXIMUM ALLOWABLE MAGNETI C

0.001 1k 10k 100k 100M1M 10M

Figure 31. Maximum Allowable External Magnetic Flux Density

MAGNETIC F I EL D F RE Q UENCY (Hz )

09292-012

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 the worst-case polarity, it reduces the received pulse from >1.0 V to 0.75 V, still well above the 0.5 V sensing threshold of the decoder.

Figure 32 shows the magnetic flux density values in terms of more familiar quantities, such as maximum allowable current flow at given distances away from the ADM3052 transformers.

1000

DISTANCE = 1m

100

DISTANCE = 5mm

10

1

0.1

MAXIMUM ALLOWABLE CURRENT (kA)

0.01

DISTANCE = 100mm

1k 10k 100k 100M1M 10M

MAGNETIC FIELD FREQUENCY (Hz)

Figure 32. Maximum Allowable Current for

Various Current-to-ADM3052 Spacings

09292-013

With combinations of strong magnetic field and high frequency, any loops formed by PCB traces can induce error voltages large enough to trigger the thresholds of succeeding circuitry. Care should be taken in the layout of such traces to avoid this possibility.

Rev. 0 | Page 16 of 20

ADM3052

APPLICATIONS INFORMATION

TYPICAL APPLICATIONS

3.3V/5V SUP P L Y

CAN

CONTROLLER

V

+SENSE

TxD

RxD

100nF

GND

1

2

C

INT

LINEAR

REGULATOR

BUS

V

+SENSE

TxD

RxD

V

REF

CAN TRANSCEIVER

REFERENCE

V

DD1

ISOLATION

BARRIER

DECODE ENCODE

ENCODE

DECODE

DIGITAL ISOLATION

V

DD2

DECODE

ENCODE

GND

LOGIC SI DE BUS SIDE

Figure 33. Typical Isolated CAN Node Using the ADM3052

1µF

RECEIVER

VOLTAGE

ADM3052

PROTECTION

DRIVER

GND

10µF

R

P

R

L

V+

CONNECTOR

V

+

CANH

CANL

V

–

100nF

BUS

09292-014

V

+R

V

+

V

DD2

CANH

CANL

V

2

REF

V

–

Rev. 0 | Page 17 of 20

ADM3052

C

OUTLINE DIMENSIONS

10.50 (0.4134)

10.10 (0.3976)

BSC

9

7.60 (0.2992)

7.40 (0.2913)

8

10.65 (0.4193)

10.00 (0.3937)

2.65 (0.1043)

2.35 (0.0925)

SEATING PLANE

8° 0°

0.33 (0.0130)

0.20 (0.0079)

0 0

.

7

.

2

(

5

0

(

5

0

.

0

2

9

5

)

.

0

9

8

)

1.27 (0.0500)

0.40 (0.0157)

45°

03-27-2007-B

0.30 (0.0118)

0.10 (0.0039)

OPLANARITY

0.10

16

1

1.27 (0.0500)

0.51 (0.0201)

0.31 (0.0122)

CONTROLLING DIMENSIONS ARE IN MILLIMETERS; INCH DIMENSIONS (IN PARENTHESES)ARE ROUNDED-OFF MILLIMETER EQUIVALENTS FOR REFERENCE ONLYAND ARE NOT APPROPRIATEFOR USE IN DESIGN.

COMPLIANT TO JEDEC STANDARDS MS-013-AA

Figure 34. 16-Lead Standard Small Outline Package [SOIC_W]

Wide Body

(RW-16)

Dimensions shown in millimeters and (inches)

ORDERING GUIDE

Model1 Temperature Range Package Description Package Option

ADM3052BRWZ −40°C to +85°C 16-Lead SOIC_W RW-16 ADM3052BRWZ-REEL7 −40°C to +85°C 16-Lead SOIC_W RW-16 EVAL-ADM3052EBZ Evaluation Board

1

Z = RoHS Compliant Part.

Rev. 0 | Page 18 of 20

ADM3052

NOTES

Rev. 0 | Page 19 of 20

ADM3052

NOTES

Rev. 0 | Page 20 of 20

Datasheet ADM3052 Datasheet (ANALOG DEVICES)

Specifications and Main Features

Frequently Asked Questions

User Manual

FEATURES

GENERAL DESCRIPTION

APPLICATIONS

FUNCTIONAL BLOCK DIAGRAM

TABLE OF CONTENTS

REVISION HISTORY

SPECIFICATIONS

TIMING SPECIFICATIONS

REGULATORY INFORMATION

INSULATION AND SAFETY-RELATED SPECIFICATIONS

VDE 0884 INSULATION CHARACTERISTICS (PENDING)

ABSOLUTE MAXIMUM RATINGS

ESD CAUTION

PIN CONFIGURATION AND FUNCTION DESCRIPTIONS

TYPICAL PERFORMANCE CHARACTERISTICS

TEST CIRCUITS

SWITCHING CHARACTERISTICS

CIRCUIT DESCRIPTION

CAN TRANSCEIVER OPERATION

ELECTRICAL ISOLATION

iCoupler Technology

TRUTH TABLES

THERMAL SHUTDOWN

LINEAR REGULATOR

MAGNETIC FIELD IMMUNITY

APPLICATIONS INFORMATION

TYPICAL APPLICATIONS

OUTLINE DIMENSIONS

ORDERING GUIDE