High Speed, ESD-Protected, Half-/Full-Duplex iCoupler Isolated RS-485 Transceiver Data Sheet ADM2491E FEATURES FUNCTIONAL BLOCK DIAGRAM V V DD1 DD2 Isolated, RS-485/RS-422 transceiver, configurable as half- or full-duplex ADM2491E 8 kV ESD protection on RS-485 input/output pins DE 16 Mbps data rate Complies with ANSI TIA/EIA RS-485-A-1998 and Y ISO 8482: 1987(E) TxD Z Suitable for 5 V or 3.3 V operation (V ) DD1 High common-mode transient immunity: >25 kV/s Receiver has open-circuit, fail-safe design A 32 nodes on the bus RxD B Thermal shutdown protection RE Safety and regulatory approvals UL recognition: 5000 V rms isolation voltage GND GND 1 2 for 1 minute, per UL 1577 Figure 1. VDE certificate of conformity DIN V VDE V 0884-10 (VDE V 0884-10): 2006-12 Reinforced insulation, V = 849 V peak IORM Operating temperature range: 40C to +85C Wide body, 16-lead SOIC package APPLICATIONS Isolated RS-485/RS-422 interfaces Industrial field networks INTERBUS Multipoint data transmission systems GENERAL DESCRIPTION The ADM2491E is an isolated data transceiver with 8 kV ESD The differential transmitter outputs and receiver inputs feature protection and is suitable for high speed, half- or full-duplex electrostatic discharge circuitry that provides protection to communication on multipoint transmission lines. For half- 8 kV using the human body model (HBM). The logic side of duplex operation, the transmitter outputs and the receiver the device can be powered with either a 5 V or a 3.3 V supply, inputs share the same transmission line. Transmitter output whereas the bus side requires an isolated 5 V supply. Pin Y is linked externally to receiver input Pin A, and transmit- The device has current-limiting and thermal shutdown features ter output Pin Z is linked to receiver input Pin B. to protect against output short circuits and situations in which The ADM2491E is designed for balanced transmission lines bus contention could cause excessive power dissipation. and complies with ANSI TIA/EIA RS-485-A-1998 and ISO The ADM2491E is available in a wide body, 16-lead SOIC package 8482: 1987(E). The device employs Analog Devices, Inc., and operates over the 40C to +85C temperature range. iCoupler technology to combine a 3-channel isolator, a three- state differential line driver, and a differential input receiver into a single package. Rev. C Document Feedback 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 20072014 Analog Devices, Inc. All rights reserved. license is granted by implication or otherwise under any patent or patent rights of Analog Devices. Technical Support www.analog.com Trademarks and registered trademarks are the property of their respective owners. GALVANIC ISOLATION 06985-001ADM2491E Data Sheet TABLE OF CONTENTS Features .............................................................................................. 1 Switching Characteristics .................................................................9 Applications ....................................................................................... 1 Typical Performance Characteristics ........................................... 10 Functional Block Diagram .............................................................. 1 Circuit Description......................................................................... 12 General Description ......................................................................... 1 Electrical Isolation ...................................................................... 12 Revision History ............................................................................... 2 Truth Tables................................................................................. 12 Specif icat ions ..................................................................................... 3 Thermal Shutdown .................................................................... 13 Timing Specifications .................................................................. 4 Fail-Safe Receiver Inputs ........................................................... 13 Package Characteristics ............................................................... 4 Magnetic Field Immunity .......................................................... 13 Regulatory Information ............................................................... 4 Applications Information .............................................................. 14 Insulation and Safety-Related Specifications ............................ 5 Isolated Power Supply Circuit .................................................. 14 VDE 0884 Insulation Characteristics ........................................ 5 PCB Layout ................................................................................. 14 Absolute Maximum Ratings ............................................................ 6 Typical Applications ................................................................... 15 ESD Caution .................................................................................. 6 Outline Dimensions ....................................................................... 16 Pin Configuration and Functional Descriptions .......................... 7 Ordering Guide .......................................................................... 16 Test Circuits ....................................................................................... 8 REVISION HISTORY 5/14Rev. B to Rev. C Changed V from 848 V peak to 849 V peak (Throughout) . 1 IORM Changes to VDE 0884 Insulation Characteristics Conditions ... 5 Changes to Ordering Guide .......................................................... 16 12/10Rev. A to Rev. B Changes to Figure 31 ...................................................................... 15 12/08Rev. 0 to Rev. A Updated Regulatory Approval Status Throughout ...................... 1 Changes to Table 7 ............................................................................ 6 10/07Revision 0: Initial Version Rev. C Page 2 of 16