DescriptionThe ST485A is a low power, high speed transceiver for RS-485 and RS-422 communications. The device contains one driver and one receiver in half duplex configuration. The ST485A draws 3 mA (typ.) of supply current when operates from a single 5 V supply.Driver is short-circuit current limited and is protected against excessive power dissipation by thermal shutdown circuitry that place the driver outputs into a high-impedance state. The receiver input has a fail-safe feature that guarantees a logic high output if both inputs are open circuit.The ST485A is designed for bi-directional data communications or multipoint bus transmission lines.DIP-8SO-8Table 1.Device summaryOrder codeTemperature rangePackagePackagingST485ABN-40 to 85 CDIP-850parts per tube / 40tube per boxST485ABDR-40 to 85 CSO-8 (Tape & reel)2500 parts per reelwww.st.comContentsST485AB2/19 Contents1Pin configuration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32Truth tabl Features Low supply current: 5 mA maxHigh data rate > 30 MbpsDesigned for RS 485 interface applications-7 to 12 common mode input voltage rangeDriver maintains high impedance in 3-state or with the power off70mV typical input hysteresisOperate from single 5 supply4 kV ESD protectionCurrent limiting and thermal shutdown for driver overload protectionLatch-up free up to 500 mADescriptionThe ST485A is a low power, high speed transceiver for RS-485 and RS-422 communications. The device contains one driver and one receiver in half duplex configuration. The ST485A draws 3 mA (typ.) of supply current when operates from a single 5 V supply.Driver is short-circuit current limited and is protected against excessive power dissipation by thermal shutdown circuitry that place the driver outputs into a high-impedance state. The receiver input has a fail-safe feature that guarantees a logic high output if both inputs are open circuit.The ST485A is designed for bi-directional data communications or mu specifications are available at: www.st