The SN65LBC176A, SN65LBC176AQ, and SN75LBC176A differential bus transceivers are monolithic, integrated circuits designed for bidirectional data communication on multipoint bus-transmission lines. They are designed for balanced transmission lines and are compatible with ANSI standard TIA/EIA-485-A and ISO 8482. The A version offers improved switching performance over its predecessors without sacrificing significantly more power. The SN65LBC176A, SN65LBC176AQ, and SN75LBC176A combine a 3-state, differential line driver and a differential input line receiver, both of which operate from a single 5-V power supply. The driver and receiver have active-high and active-low enables, respectively, which can externally connect together to function as a direction control. The driver differential outputs and the receiver differential inputs connect internally to form a differential input /output (I/O) bus port that is designed to offer minimum loading to the bus whenever the driver is disabled or VCC = 0. This port features wide positive and negative common-mode voltage ranges, making the device suitable for party-line applications. Very low device supply current can be achieved by disabling the driver and the receiver.