DS1487

DS1487 Low Power RS-485 January 1997 DS1487 Low Power RS-485 General Description Unit Load Multipoint Transceiver Features Y Y Y Y Y Y Y The DS1487 is a low-power transceiver for RS-485 and RS-422 communication The device contains one driver and one receiver The drivers slew rate allows for operation up to 2 0 Mbps (see Applications Information section) The transceiver presents unit loading to the RS-485 bus allowing up to 128 nodes to be connected together without the use of repeaters The transceiver draws 200 mA of supply current when unloaded or fully loaded with the driver disabled and operates from a single a 5V supply The driver is short-circuit current limited and is protected against excessive power dissipation by thermal shutdown circuitry that places the driver outputs into TRI-STATE www.DataSheet4U.com (High Impedance state) under fault conditions The driver guarantees a minimum of 1 5V differential output voltage with maximum loading across the common mode range (VOD3) The receiver has a failsafe feature that guarantees a logichigh output if the input is open circuit The DS1487 is available in surface mount and DIP packages Y Y Y Y Meets TIA EIA RS-485 multipoint standard Allows up to 128 transceivers on the bus ( U L ) Guaranteed full load output voltage (VOD3) Low quiescent current 200 mA typ b 7V to a 12V common-mode input voltage range TRI-STATE outputs on driver and receiver AC performance Driver transition time 25 ns typ Driver propagation delay 40 ns...