GENERAL DESCRIPTION
The ADM1486 is a differential line transceiver suitable for high speed bidirectional data communication on multipoint bus transmission lines. It is designed for balanced data transmission, complies with EIA Standards RS-485 and RS-422 and is recommended for PROFIBUS applications. The part contains a differential line driver and a differential line receiver. Both the driver and the receiver may be enabled independently. When disabled or with power off, the driver outputs are tristated.
The ADM1486 operates from a single +5 V power supply. Excessive power dissipation caused by bus contention or by output shorting is prevented by a thermal shutdown circuit. This feature forces the driver output into a high impedance state if during fault conditions a significant temperature increase is detected in the internal driver circuitry.
Up to 50 transceivers may be connected simultaneously on a bus, but only one driver should be enabled at any time. It is important therefore that the remaining disabled drivers do not load the bus. To ensure this, the ADM1486 driver features high output impedance when disabled and also when powered down.
This minimizes the loading effect when the transceiver is not being utilized. The high impedance driver output is maintained over the entire common-mode voltage range from –7 V to +12 V.
The receiver contains a fail safe feature which results in a logic high output state if the inputs are unconnected (floating).

FEATURES
  Meets & Exceeds EIA RS-485 & EIA RS-422 Standard
  50 Mb/s Data Rate
  Recommended for PROFIBUS Applications
  2.1V Minimum Differential Output with 54

  Termination
  Low Power 0.5mA ICC
  Thermal Shutdown & Short Circuit Protection
  Zero Skew Driver & Receiver
  Driver Propagation Delay: 8 ns
  Receiver Propagation Delay: 12 ns
  High Z Outputs with Drivers Disabled or Power Off
  Superior Upgrade for SN65ALS1176
  15kV HBM ESD Protection on I/O Pins A & B
  Available in Standard 8-pin SOIC & Miniature 8-pin
  Micro SOIC packages

APPLICATIONS
  Industrial Field Equipment