IThe SIT3491EESD is a fully integrated RS-485/RS-422 IC, manufactured by SITI, that is housed in a SOP-14 (small outline package) and is compliant with the RoHS (Restriction of Hazardous Substances) directive. It offers easy-to-implement, high performance, fault-tolerant data communications designed for a wide range of industrial automation and computer systems applications. The SIT3491EESD IC provides a half-duplex or full-duplex two-wire or four-wire RS-485/RS-422 interface. It offers high serial data rate up to 250Kbps and provides up to 256 nodes in data networks. It also includes a fail-safe receiver which turns the bus into a high impedance state when it is not receiving data. With its 5.0V tolerant I/O pins, it is ideal for use in systems powered with +5V and +3.3V rails.