ANALOG DEVICES ADM2682E, ADM2687E Service Manual

5 kV rms Signal and Power Isolated

V

V

RS-485 Transceiver with ±15 kV ESD

FEATURES

5 kV rms isolated RS-485/RS-422 transceiver, configurable as

half or full duplex

isoPower integrated isolated dc-to-dc converter
±15 kV ESD protection on RS-485 input/output pins
Complies with ANSI/TIA/EIA-485-A-98 and ISO 8482:1987(E)
Data rate: 16 Mbps (ADM2682E), 500 kbps (ADM2687E)
5 V or 3.3 V operation
Connect up to 256 nodes on one bus
Open- and short-circuit, fail-safe receiver inputs
High common-mode transient immunity: >25 kV/μs
Thermal shutdown protection
Safety and regulatory approvals

UL recognition (pending)

5000 V rms for 1 minute per UL 1577

CSA Component Acceptance Notice #5A (pending)

IEC 60601-1: 400 V rms (basic), 250 V rms (reinforced)
IEC 60950-1: 600 V rms (basic), 380 V rms (reinforced)

VDE Certificates of Conformity (pending)

DIN EN 60747-5-2 (VDE 0884 Part 2): 2003-01
V

= 846 V peak

IORM

Operating temperature range: −40°C to +85°C
16-lead wide-body SOIC with >8 mm creepage and clearance

APPLICATIONS

Isolated RS-485/RS-422 interfaces
Industrial field networks
Multipoint data transmission systems

CC

DIGITAL ISOLATION iCou pler

TxD

DE

RxD

RE

ADM2682E/ADM2687E

FUNCTIONAL BLOCK DIAGRAM

ISOOUT

isoPower DC-TO-DC CONVERTER

OSCILLATOR

ENCODE

ENCODE

DECODE

GND

1

ISOLATION

BARRIER

Figure 1.

RECTIFIER

REGULATOR

TRANSCEIVER

DECODE D

DECODE

ENCODE

ADM2682E/ADM2687E

GND

V

ISOIN

Y

Z

R

2

A

B

09927-001

GENERAL DESCRIPTION

The ADM2682E/ADM2687E are fully integrated 5 kV rms
signal and power isolated data transceivers with ±15 kV ESD
protection and are suitable for high speed communication on
multipoint transmission lines. The ADM2682E/ADM2687E
include an integrated 5 kV rms isolated dc-to-dc power supply
that eliminates the need for an external dc-to-dc isolation block.

They are designed for balanced transmission lines and comply
with ANSI/TIA/EIA-485-A-98 and ISO 8482:1987(E).

The devices integrate Analog Devices, Inc., iCoupler® technology to
combine a 3-channel isolator, a three-state differential line driver, a
differential input receiver, and Analog Devices isoPower® dc-to-dc
converter into a single package. The devices are powered by a
single 5 V or 3.3 V supply, realizing a fully integrated signal and
power isolated RS-485 solution.

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.

The ADM2682E/ADM2687E drivers have an active high enable.
An active low receiver enable is also provided, which causes the
receiver output to enter a high impedance state when disabled.

The devices have current limiting and thermal shutdown
features to protect against output short circuits and situations
where bus contention may cause excessive power dissipation.
The parts are fully specified over the industrial temperature
range and are available in a highly integrated, 16-lead, wide­body SOIC package with >8 mm creepage and clearance.

The ADM2682E/ADM2687E contain 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

AN-0971 Application Note, Recommendations for Control of

Radiated Emissions with isoPower Devices, for details on board
layout considerations.

One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106, U.S.A.
Tel: [phone] www.analog.com
Fax: [phone] ©2011 Analog Devices, Inc. All rights reserved.

ADM2682E/ADM2687E

TABLE OF CONTENTS

Features.............................................................................................. 1

Applications....................................................................................... 1

Functional Block Diagram .............................................................. 1

General Description ......................................................................... 1

Revision History ............................................................................... 2

Specifications..................................................................................... 3

ADM2682E Timing Specifications ............................................ 4

ADM2687E Timing Specifications ............................................ 4

Package Characteristics ............................................................... 4

Regulatory Information............................................................... 5

Insulation and Safety-Related Specifications............................ 5

VDE 0884 Insulation Characteristics (Pending)...................... 6

Absolute Maximum Ratings............................................................ 7

ESD Caution.................................................................................. 7

Pin Configuration and Function Descriptions............................. 8

Typical Performance Characteristics ............................................. 9

Test Circuits..................................................................................... 14

Switching Characteristics .............................................................. 15

Circuit Description......................................................................... 16

Signal Isolation ........................................................................... 16

Power Isolation ........................................................................... 16

Truth Tables................................................................................. 16

Thermal Shutdown .................................................................... 16

Open- and Short-Circuit, Fail-Safe Receiver Inputs.............. 16

DC Correctness and Magnetic Field Immunity........................... 16

Applications Information.............................................................. 18

PCB Layout ................................................................................. 18

EMI Considerations................................................................... 18

Insulation Lifetime..................................................................... 19

Isolated Supply Considerations................................................ 19

Typical Applications................................................................... 20

Outline Dimensions....................................................................... 22

Ordering Guide .......................................................................... 22

REVISION HISTORY

7/11—Revision 0: Initial Version

Rev. 0 | Page 2 of 24

ADM2682E/ADM2687E

SPECIFICATIONS

All voltages are relative to their respective ground; 3.0 ≤ VCC ≤ 5.5 V. All minimum/maximum specifications apply over the entire
recommended operation range, unless otherwise noted. All typical specifications are at T

Table 1.

Parameter Symbol Min Typ Max Unit Test Conditions/Comments

ADM2687E SUPPLY CURRENT ICC

Data Rate ≤ 500 kbps 90 mA VCC = 3.3 V, 100 Ω load between Y and Z
72 mA VCC = 5 V, 100 Ω load between Y and Z
125 mA VCC = 3.3 V, 54 Ω load between Y and Z
98 mA VCC = 5 V, 54 Ω load between Y and Z

140 mA 120 Ω load between Y and Z

ADM2682E SUPPLY CURRENT ICC

Data Rate = 16 Mbps 175 mA 120 Ω load between Y and Z
260 mA 54 Ω load between Y and Z

Data Rate = 16 Mbps, 4.5 ≤ VCC ≤ 5.5 V 130 mA 120 Ω load between Y and Z
200 mA 54 Ω load between Y and Z
ISOLATED SUPPLY VOLTAGE V

3.3 V

ISOOUT

DRIVER

Differential Outputs

Differential Output Voltage, Loaded |V

| 2.0 3.6 V RL = 100 Ω (RS-422), see Figure 29

OD2

1.5 3.6 V RL = 54 Ω (RS-485), see Figure 29
|V

| 1.5 3.6 V −7 V ≤ V

OD3

Δ|VOD| for Complementary Output States Δ|VOD| 0.2 V RL = 54 Ω or 100 Ω, see Figure 29
Common-Mode Output Voltage VOC 3.0 V RL = 54 Ω or 100 Ω, see Figure 29
Δ|VOC| for Complementary Output States Δ|VOC| 0.2 V RL = 54 Ω or 100 Ω, see Figure 29
Short-Circuit Output Current IOS 200 mA

Output Leakage Current (Y, Z) IO 30 μA

−30 μA

Logic Inputs DE, RE, TxD

Input Threshold Low VIL 0.27 VCC V
Input Threshold High VIH 0.7 VCC V
Input Current II −10 0.01 10 μA

RECEIVER

Differential Inputs

Differential Input Threshold Voltage VTH −200 −125 −30 mV −7 V < VCM < +12 V
Input Voltage Hysteresis V

15 mV VOC = 0 V

HYS

Input Current (A, B) II 125 μA DE = 0 V, VCC = 0 V or 3.6 V, VIN = 12 V

−100 μA DE = 0 V, VCC = 0 V or 3.6 V, VIN = −7 V
Line Input Resistance RIN 96 kΩ −7 V < VCM < +12 V

Logic Outputs

Output Voltage Low VOL 0.2 0.4 V IO = 1.5 mA, VA − VB = −0.2 V
Output Voltage High VOH V

− 0.3 VCC − 0.2 V IO = −1.5 mA, VA − VB = 0.2 V

CC

Short-Circuit Current 100 mA

COMMON-MODE TRANSIENT IMMUNITY1 25 kV/μs VCM = 1 kV, transient magnitude = 800 V

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.

= 25°C, VCC = 5 V unless otherwise noted.

A

≤ 12 V, see Figure 30

TEST1

DE = 0 V, RE

= 0 V, VCC = 0 V or 3.6 V,

VIN = 12 V
DE = 0 V, RE

= 0 V, VCC = 0 V or 3.6 V,

VIN = −7 V

, TxD

DE, RE

, TxD

DE, RE

, TxD

DE, RE

Rev. 0 | Page 3 of 24

ADM2682E/ADM2687E

ADM2682E TIMING SPECIFICATIONS

TA = −40°C to +85°C.

Table 2.

Parameter Symbol Min Typ Max Unit Test Conditions/Comments

DRIVER

Maximum Data Rate 16 Mbps
Propagation Delay, Low to High t
Propagation Delay, High to Low t
Output Skew t
Rise Time/Fall Time tDR, tDF 15 ns RL = 54 Ω, CL1 = CL2 = 100 pF, see Figure 31 and Figure 35
Enable Time tZL, tZH 120 ns RL = 110 Ω, CL = 50 pF, see Figure 32 and Figure 37
Disable Time tLZ, tHZ 150 ns RL = 110 Ω, CL = 50 pF, see Figure 32 and Figure 37

RECEIVER

Propagation Delay, Low to High t
Propagation Delay, High to Low t
Output Skew1 t
Enable Time tZL, tZH 15 ns RL = 1 kΩ, CL = 15 pF, see Figure 34 and Figure 38
Disable Time tLZ, tHZ 15 ns RL = 1 kΩ, CL = 15 pF, see Figure 34 and Figure 38

1

Guaranteed by design.

ADM2687E TIMING SPECIFICATIONS

TA = −40°C to +85°C.

Table 3.

Parameter Symbol Min Typ Max Unit Test Conditions/Comments

DRIVER

Maximum Data Rate 500 kbps
Propagation Delay, Low to High t
Propagation Delay, High to Low t
Output Skew t
Rise Time/Fall Time tDR, tDF 200 1100 ns RL = 54 Ω, CL1 = CL2 = 100 pF, see Figure 31 and Figure 35
Enable Time tZL, tZH 2.5 μs RL = 110 Ω, CL = 50 pF, see Figure 32 and Figure 37
Disable Time tLZ, tHZ 200 ns RL = 110 Ω, CL = 50 pF, see Figure 32 and Figure 37

RECEIVER

Propagation Delay, Low to High t
Propagation Delay, High to Low t
Output Skew t
Enable Time tZL, tZH 15 ns RL = 1 kΩ, CL = 15 pF, see Figure 34 and Figure 38
Disable Time tLZ, tHZ 15 ns RL = 1 kΩ, CL = 15 pF, see Figure 34 and Figure 38

63 100 ns RL = 54 Ω, CL1 = C

DPLH

64 100 ns RL = 54 Ω, CL1 = C

DPHL

1 8 ns RL = 54 Ω, CL1 = CL2 = 100 pF, see Figure 31 and Figure 35

SKEW

94 110 ns CL = 15 pF, see Figure 33 and Figure 36

RPLH

95 110 ns CL = 15 pF, see Figure 33 and Figure 36

RPHL

1 12 ns CL = 15 pF, see Figure 33 and Figure 36

SKEW

250 503 700 ns RL = 54 Ω, CL1 = C

DPLH

250 510 700 ns RL = 54 Ω, CL1 = C

DPHL

7 100 ns RL = 54 Ω, CL1 = CL2 = 100 pF, see Figure 31 and Figure 35

SKEW

91 200 ns CL = 15 pF, see Figure 33 and Figure 36

RPLH

95 200 ns CL = 15 pF, see Figure 33 and Figure 36

RPHL

4 30 ns CL = 15 pF, see Figure 33 and Figure 36

SKEW

= 100 pF, see Figure 31 and Figure 35

L2

= 100 pF, see Figure 31 and Figure 35

L2

= 100 pF, see Figure 31 and Figure 35

L2

= 100 pF, see Figure 31 and Figure 35

L2

PACKAGE CHARACTERISTICS

Table 4.

Parameter Symbol Min Typ Max Unit Test Conditions/Comments

Resistance (Input-to-Output)1 R
Capacitance (Input-to-Output)1 C
Input Capacitance2 C

1

Device considered a 2-terminal device: short together Pin 1 to Pin 8 and short together Pin 9 to Pin 16.

2

Input capacitance is from any input data pin to ground.

10

I-O

3 pF f = 1 MHz

I-O

4 pF

I

Rev. 0 | Page 4 of 24

12

Ω

ADM2682E/ADM2687E

REGULATORY INFORMATION

Table 5. ADM2682E/ADM2687E Approvals (Pending)

Organization Approval Type
UL (Pending)

CSA (Pending)

VDE (Pending)

INSULATION AND SAFETY-RELATED SPECIFICATIONS

Table 6.

Parameter Symbol Value Unit Test Conditions/Comments

Rated Dielectric Insulation Voltage 5000 V rms 1-minute duration
Minimum External Air Gap (Clearance) L(I01) >8.0 mm

Minimum External Tracking (Creepage) L(I02) >8.0 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 0110:1989-01, Table 1)

To be recognized under the UL 1577 Component Recognition Program of Underwriters Laboratories, Inc.
Single protection, 5000 V rms isolation voltage.
In accordance with UL 1577, each ADM2682E/ADM2687E is proof tested by applying an insulation test voltage

≥ 6000 V rms for 1 second.
To be approved under CSA Component Acceptance Notice #5A.
Reinforced insulation per IEC 60601-1, 250 V rms (353 V peak) maximum working voltage.
Basic insulation per IEC 60601-1, 400 V rms (566 V peak) maximum working voltage.
Reinforced insulation per CSA 60950-1-07 and IEC 60950-1, 380 V rms (537 V peak) maximum working voltage.
Basic insulation per CSA 60950-1-07 and IEC 60950-1, 600 V rms (848 V peak) maximum working voltage.
To be certified according to DIN EN 60747-5-2 (VDE 0884 Part 2):2003-01.
In accordance with DIN EN 60747-5-2, each ADM2682E/ADM2687E is proof tested by applying an insulation test voltage

≥1590 V peak for 1 second.

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 5 of 24

ADM2682E/ADM2687E

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 7.

Description Test Conditions/Comments Symbol Characteristic Unit

CLASSIFICATIONS

Installation Classification per DIN VDE 0110 for

Rated Mains Voltage
≤300 V rms I to IV
≤450 V rms I to III
≤600 V rms I to II

Climatic Classification 40/85/21
Pollution Degree Table 1 of DIN VDE 0110 2

VOLTAGE

Maximum Working Insulation Voltage V
Input-to-Output Test Voltage VPR

Method b1

Method a

After Environmental Tests, Subgroup 1 V

After Input and/or Safety Test,

Subgroup 2/Subgroup 3

Highest Allowable Overvoltage Transient overvoltage, tTR = 10 sec VTR 6000 V peak

SAFETY-LIMITING VALUES Maximum value allowed in the event of a failure

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

846 V peak

IORM

× 1.875 = VPR, 100% production tested,

V

IORM

= 1 sec, partial discharge < 5 pC

t

m

× 1.6 = VPR, tm = 60 sec, partial discharge < 5 pC 1375 V peak

IORM

× 1.2 = VPR, tm = 60 sec, partial discharge < 5 pC 1018 V peak

V

IORM

= 500 V RS >109 Ω

IO

1590 V peak

265 mA

S, INPUT

335 mA

S, OUTPUT

Rev. 0 | Page 6 of 24

ADM2682E/ADM2687E

ABSOLUTE MAXIMUM RATINGS

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

Table 8.

Parameter Rating
VCC −0.5 V to +7 V
Digital Input Voltage (DE, RE, TxD)
Digital Output Voltage (RxD) −0.5 V to VDD + 0.5 V
Driver Output/Receiver Input Voltage −9 V to +14 V
Operating Temperature Range −40°C to +85°C
Storage Temperature Range −55°C to +150°C
ESD (Human Body Model) on

A, B, Y, and Z pins
ESD (Human Body Model) on Other Pins
Thermal Resistance θJA
Lead Temperature

Soldering (10 sec) 260°C

Vapor Phase (60 sec) 215°C

Infrared (15 sec) 220°C

−0.5 V to V

±15 kV

±2 kV
52°C/W

+ 0.5 V

DD

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.

Table 9. Maximum Continuous Working Voltage

Parameter Max Unit Reference Standard

AC Voltage

Bipolar Waveform 424 V peak

Unipolar Waveform

Basic Insulation 600 V peak
Reinforced Insulation 537 V peak

DC Voltage

Basic Insulation 600 V peak
Reinforced Insulation 537 V peak

1

Refers to continuous voltage magnitude imposed across the isolation

barrier. See the Insulation Lifetime section for more details.

ESD CAUTION

1

All certifications,
50-year minimum
lifetime

Maximum approved
working voltage per
IEC 60950-1

Maximum approved
working voltage per
IEC 60950-1

Rev. 0 | Page 7 of 24

ADM2682E/ADM2687E

PIN CONFIGURATION AND FUNCTION DESCRIPTIONS

1

GND

1

V

2

CC

3

RxD

TxD

V

GND

NOTES

1. PIN 10 AND PIN 15 M UST BE
CONNECTED EXT ERNALLY.

RE

DE

CC

1

ADM2682E/

4

ADM2687E

5

TOP VIEW

(Not to Scale)

6

7

8

16

GND

2

V

15

ISOIN

14

A

B

13

12

Z

Y

11

10

V

ISOOUT

GND

9

2

09927-002

Figure 2. Pin Configuration

Table 10. Pin Function Descriptions

Pin No. Mnemonic Description

1 GND1 Ground, Logic Side.
2 V

CC

Logic Side Power Supply. It is recommended that a 0.1 μF and a 0.01 μF decoupling capacitor be fitted between
Pin 2 and Pin 1.

3 RxD

4

Receiver Enable Input. This is an active-low input. Driving this input low enables the receiver, while driving it high

RE

Receiver Output Data. This output is high when (A − B) ≥ −30 mV and low when (A − B) ≤ –200 mV. The output is
tristated when the receiver is disabled, that is, when RE

is driven high.

disables the receiver.
5 DE Driver Enable Input. Driving this input high enables the driver, while driving it low disables the driver.
6 TxD Driver Input. Data to be transmitted by the driver is applied to this input.
7 V

CC

Logic Side Power Supply. It is recommended that a 0.1 μF and a 10 μF decoupling capacitor be fitted between

Pin 7 and Pin 8.
8 GND1 Ground, Logic Side.
9 GND2 Ground, Bus Side.
10 V

ISOOUT

Isolated Power Supply Output. This pin must be connected externally to V

. It is recommended that a reservoir

ISOIN

capacitor of 10 μF and a decoupling capacitor of 0.1 μF be fitted between Pin 10 and Pin 9.
11 Y Driver Noninverting Output
12 Z Driver Inverting Output
13 B Receiver Inverting Input.
14 A Receiver Noninverting Input.
15 V

ISOIN

Isolated Power Supply Input. This pin must be connected externally to V

. It is recommended that a 0.1 μF

ISOOUT

and a 0.01 μF decoupling capacitor be fitted between Pin 15 and Pin 16.
16 GND2 Ground, Bus Side.

Rev. 0 | Page 8 of 24