The ADM1486 is a differential line transceiver suitable for high speed bidirectional data communication on multipoint bus transmission lines. It is designed for balanced data transmission, complies with EIA Standards RS-485 and RS-422 and is recommended for PROFIBUS applications. The part contains a differential line driver and a differential line receiver. Both the driver and the receiver may be enabled independently. When disabled or with power off, the driver outputs are tristated. The ADM1486 operates from a single +5 V power supply. Excessive power dissipation caused by bus contention or by output shorting is prevented by a thermal shutdown circuit. This feature forces the driver output into a high impedance state if during fault conditions a significant temperature increase is detected in the internal driver circuitry.