PRELIMINARY TECHNICAL DATA

a

High-Speed(10Mbps),Fail-Safe,RS-485/RS-422

TransceiverswithSlew-Rate-Limiting

and±15kVESD Protection

ADM3082/ADM3085/ADM3088

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reliable. However, no responsibility is assumed by Analog Devices for its

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which may result from its use. No license is granted by implication or

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© Analog Devices, Inc., 2002

GENERAL

DESCRIPTION

The ADM3082/ADM3085/ADM3088 are high-speed

RS-485/RS-422 transceivers consisting of one driver and one

receiver per package. The devices feature fail-safe operation,

ensuring a logic-high receiver output when the receiver in-

puts are open-circuit or short-circuit. This guarantees that

the receiver output will be high if all the transmitters on a

terminated bus are disabled (high-impedance).

The ADM3082 has a slew-rate limited driver to minimize

electromagnetic interference (EMI) and reduce reflections

caused by incorrectly terminated cables. This allows error-

free transmission at data rates up to 115kbps.

The ADM3085 offers a higher slew rate allowing data rates

up to 500kbps, while the ADM3088 has a driver whose slew

rate is not limited, allowing data rates up to 10Mbps.

All devices in the family feature ±15kV electrostatic dis-

charge (ESD) protection and high receiver input imped-

ance (1/8 unit load), allowing up to 256 transceivers on

the bus. The devices have low current drain of 375µA un-

loaded, or fully loaded with the drivers disabled, and fea-

ture an ultra-low power (1nA) shutdown mode.

FEATURES

Enhanced Slew Rate Limiting for Error-Free Data

Transmission

Fail-Safe Receiver Operation while Maintaining

EIA/TIA-485 compatibility

Low-Current (1nA) Shutdown Mode

High Input Impedance — Up to 256 Transceivers on Bus

±15kV ESD Protection (Human Body Model) on

RS-485 I/O pins

Pin-Compatible with Industry Standard 75176

APPLICATIONS

Enhanced Replacement for Industry-Standard Parts

EMI-Sensitive Systems

Level Translation

LANs for Industrial Control Applications

FUNCTIONAL BLOCK DIAGRAM

1

2

3

4

8

7

6

5

D

R

RO

RE

DE

DI

B

A

GND

AD M30 82/A D M308 5/AD M 3088

REV. PrA 02/02