2.5 kV Isolated RS-485 Transceivers with Integrated Transformer Driver ADM2482E/ADM2487E FEATURES FUNCTIONAL BLOCK DIAGRAM V D1 D2 V DD1 DD2 Isolated RS-485/RS-422 transceivers, configurable as half duplex or full duplex OSC Integrated oscillator driver for external transformer DE 15 kV ESD protection on RS-485 input/output pins Complies with TIA/EIA-485-A-98 and ISO 8482:1987(E) Y TxD Data rate: 500 kbps/16 Mbps Z 5 V or 3.3 V operation (V ) DD1 256 nodes on bus A True fail-safe receiver inputs RxD B Safety and regulatory approvals RE UL recognition: 2500 V rms for 1 minute per UL 1577 VDE certificates of conformity GND GND 1 2 DIN VVDE V 0884-10 (VDE V 0884-10):2006-12 Figure 1. V = 560 V peak IORM Thermal shutdown protection Operating temperature range: 40C to +85C Wide-body, 16-lead SOIC package APPLICATIONS Isolated RS-485/RS-422 interfaces Industrial field networks Multipoint data transmission systems GENERAL DESCRIPTION The ADM2482E/ADM2487E are isolated data transceivers with power. The logic side of the device is powered with either a 5 V 15 kV ESD protection and are suitable for high speed, half- or a 3.3 V supply, and the bus side is powered with an isolated duplex or full-duplex communication on multipoint transmission 3.3 V supply. lines. For half-duplex operation, the transmitter outputs and The ADM2482E/ADM2487E driver has an active high enable, receiver inputs share the same transmission line. Transmitter and the receiver has an active low enable. The driver output Output Pin Y is linked externally to Receiver Input Pin A, and enters a high impedance state when the driver enable signal Transmitter Output Pin Z to Receiver Input Pin B. The parts are is low. The receiver output enters a high impedance state when designed for balanced transmission lines and comply with the receiver enable signal is high. TIA/EIA-485-A-98 and ISO 8482:1987(E). The device has current-limiting and thermal shutdown features The devices employ the Analog Devices, Inc., iCoupler to protect against output short circuits and situations where bus technology to combine a 3-channel isolator, a three-state contention might cause excessive power dissipation. The part is differential line driver, and a differential input receiver into a fully specified over the industrial temperature range of 40C to single package. An on-chip oscillator outputs a pair of square +85C and is available in a 16-lead, wide-body SOIC package. waveforms that drive an external transformer to provide isolated Rev. A 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 One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106, U.S.A. rights of third parties that may result from its use. Specifications subject to change without notice. No Tel: 781.329.4700 www.analog.com license is granted by implication or otherwise under any patent or patent rights of Analog Devices. Fax: 781.461.3113 20082009 Analog Devices, Inc. All rights reserved. Trademarks and registered trademarks are the property of their respective owners. GALVANIC ISOLATION 07379-001ADM2482E/ADM2487E TABLE OF CONTENTS Features .............................................................................................. 1 Test Circuits ..................................................................................... 12 Applications ....................................................................................... 1 Switching Characteristics .............................................................. 13 Functional Block Diagram .............................................................. 1 Circuit Description......................................................................... 14 General Description ......................................................................... 1 Electrical Isolation ...................................................................... 14 Revision History ............................................................................... 2 Truth Tables................................................................................. 14 Specif icat ions ..................................................................................... 3 Thermal Shutdown .................................................................... 15 Timing Specifications .................................................................. 4 True Fail-Safe Receiver Inputs .................................................. 15 Package Characteristics ............................................................... 5 Magnetic Field Immunity .......................................................... 15 Regulatory Information ............................................................... 5 Applications Information .............................................................. 16 Insulation and Safety-Related Specifications ............................ 5 Printed Circuit Board Layout ................................................... 16 VDE 0884-2 Insulation Characteristics ..................................... 6 Transformer Suppliers ............................................................... 16 Absolute Maximum Ratings ............................................................ 7 Isolated Power Supply Circuit .................................................. 16 ESD Caution .................................................................................. 7 Typical Applications ................................................................... 17 Pin Configuration and Function Descriptions ............................. 8 Outline Dimensions ....................................................................... 18 Typical Performance Characteristics ............................................. 9 Ordering Guide .......................................................................... 18 REVISION HISTORY 2/09Rev. 0 to Rev. A Edits to Features ................................................................................ 1 Added Table 5 .................................................................................... 5 Changes to Table 6 ............................................................................ 5 Added Table 7 .................................................................................... 6 Changes to Figure 9 ........................................................................ 13 Added Table 13 ............................................................................... 16 Changes to Ordering Guide .......................................................... 18 5/08Revision 0: Initial Version Rev. A Page 2 of 20