HI-8685 / HI-8686

The HI-8685 and HI-8686 are system components for interfacing incoming ARINC 429 signals to 16-bit parallel data using proven +5V analog/digital CMOS technology. Both products incorporate the digital logic and analog line receiver circuitry in a single device.

The receivers on the HI-8685 and the HI-8686 connect directly to the ARINC 429 Bus and translate the incoming signals to normal CMOS levels. Internal comparator levels are set just below the standard 6.5 volt minimum data threshold and just above the standard 2.5 volt maximum null threshold. The -10 version of the HI-8685 allows the incorporation of an external 10Kohm resistance in series with each ARINC input for lightning protection without affecting ARINC level detection.

Both products offer high speed 16-bit parallel bus interface, a 32-bit buffer, and error detection for word length and parity. A reset pin is also provided for power-on initialization.



  • Automatic Conversion of Serial ARINC 429, 575 & 561 Data to 16-Bit Parallel Data
  • High Speed Parallel 16-Bit Data Bus
  • Error Detection - Word Length and Parity
  • Reset Input for Power-On Initialization
  • On-Chip Line Receiver connects directly to ARINC bus
  • Internal Lightning Protection of ARINC inputs in accordance with DO-160D, Level 3 (-10 options only)
  • Input Hysteresis of at Least 2 Volts
  • Test Inputs Bypass Analog Inputs
  • Simplified Lightning Protection With the Ability to Add 10 Kohm External Series Resistors
  • Small Surface Mount, Plastic Package Options: SOIC, TQFP and PLCC
  • Industrial & Extended Temperature Ranges Available



  • Avionics Data Communication
  • Serial to Parallel Conversion