5 V Low Power, Slew-Rate Limited RS-485/RS-422 Transceiver ADM483 FEATURES FUNCTIONAL BLOCK DIAGRAM V EIA RS-485/RS-422-compliant CC Data rates up to 250 kbps ADM483 Slew-rate limited for low EMI 100 nA supply current in shutdown mode RO R Low power consumption (120 A) A RE Up to 32 transceivers on one bus B Outputs high-z when disabled or powered off DE 7 V to +12 V bus common-mode range DI D Thermal shutdown and short-circuit protection Pin-compatible with MAX483 GND Specified over 40C to +85C temperature range Available in 8-lead SOIC package Figure 1. APPLICATIONS Low power RS-485 applications EMI sensitive systems DTE-DCE interfaces Industrial control Packet switching Local area networks Level translators GENERAL DESCRIPTION The ADM483 is a low power differential line transceiver suitable The receiver contains a fail-safe feature that results in a logic for half-duplex data communication on multipoint bus trans- high output state if the inputs are unconnected (floating). mission lines. It is designed for balanced data transmission, and The driver outputs are slew-rate limited to reduce EMI and data complies with EIA Standards RS-485 and RS-422.The part errors caused by reflections from improperly terminated buses. contains a differential line driver and a differential line receiver. Excessive power dissipation caused by bus contention or by Both share the same differential pins, with either the driver or output shorting is prevented by a thermal shutdown circuit. the receiver being enabled at any given time. The part is fully specified over the industrial temperature range, The device has an input impedance of 12 k, a llowing up to and is available in an 8-lead SOIC package. 32 transceivers on one bus. Since only one driver should be enabled at any time, the output of a disabled or powered-down driver is three-stated to avoid overloading the bus. This high impedance driver output is maintained over the entire common-mode voltage range from 7 V to +12 V. 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. One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106, U.S.A. Specifications subject to change without notice. No license is granted by implication Tel: 781.329.4700 www.analog.com or otherwise under any patent or patent rights of Analog Devices. Trademarks and registered trademarks are the property of their respective owners. Fax: 781.326.8703 2004 Analog Devices, Inc. All rights reserved. 05079-001ADM483 TABLE OF CONTENTS Specifications..................................................................................... 3 Applications..................................................................................... 11 Timing Specifications....................................................................... 4 Differential Data Transmission ................................................ 11 Absolute Maximum Ratings............................................................ 5 Cable and Data Rate................................................................... 11 ESD Caution.................................................................................. 5 Thermal Shutdown .................................................................... 12 Pin Configuration and Function Descriptions............................. 6 Receiver Open-Circuit Fail-Safe............................................... 12 Test Circuits....................................................................................... 7 Outline Dimensions ....................................................................... 13 Switching Characteristics ................................................................ 8 Ordering Guide .......................................................................... 13 Typical Performance Characteristics ............................................. 9 REVISION HISTORY 10/04Revision 0: Initial Version Rev. 0 Page 2 of 16