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 powered down，the driver outputs are high impedance. The ADM1486 operates from a single 5 V power supply. Excessive power dissipation caused by bus contention or output shorting is prevented by short-circuit protection and thermal circuitry. Short-circuit protection circuits limit the maximum output current to ±200 mA during fault conditions.A thermal shutdown circuit senses if the die temperature rises above 150°C and forces the driver outputs into a high impedance state under this condition. Up to 50 transceivers may be connected simultaneously on a bus， but only one driver should be enabled at a time. Therefore， it is important that the remaining disabled drivers do not load the bus