Fail-safe Differential Bus Transceiver

The SN75276 differential Bus Transceiver is a monolithic, integrated circuit designed for bidirectional data Communication on multipoint bus transmission lines. It is designed for balanced transmission lines and is electrically compatible with ANSI Standards TIA/EIA-422-B and TIA/EIA-485-A, and meets ITU Recommendation V.11. The fail-safe operation ensures a known level on the circuit output under bus fault conditions. The circuit provides a high-level output under floating-line, idle-line, open-circuit, and short-circuit bus conditions (see Function Tables). The SN75276 combines 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, that CAN be externally connected together to function as a direction control. The driver differential outputs and the receiver differential inputs are connected internally to form differential input/output (I/O) bus ports that are designed to offer minimum loading to the bus whenever the driver is disabled or VCC = 0. These ports feature wide positive and negative common-mode voltage ranges making the device suitable for party-line applications. By STMicroelectronics