NEXSYS® Component Technology – Sensors & Detectors

ARINC 429 Multi-Bit Binary Decoder

ARINC 429 Signal Converter

The ARINC 429 Multi-Bit Binary Decoder (SR429/4D) from Applied Avionics can provide a full binary decode for up to three bits from a single ARINC 429 data label. The 2 X 4 decoder option is available in an 8-pin package (expandable to 12-pin) while the 3 X 8 decoder is a 12-pin device. The polarity of the decoded outputs is selectable (one selection for all decoded results).

The ARINC converter circuitry inside the SR429/4D includes an internal Health Monitor that can provide a “fail” indication if power to the decoder is lost or upon loss of valid ARINC data input. The Health Monitor has a range of watchdog timings requiring a valid ARINC label to be received within a specified time interval. If specified, the Health Monitor can be selected as a decoder input.

  • No software, firmware or programmable logic.
  • No stand-alone decoder required to achieve annunciation based on data bits.
  • Watchdog timer available to monitor validity of incoming ARINC data stream.

How it Works

2 X 4 Decoder

Two specified ARINC data bits are input to the 2 X 4 decoder producing four binary results on four separate output pins. Output polarity for the decoded bits can be specified as Open = True or Ground = True.

Additional Options

  • Within the same 8-pin package, repurpose decoder answer “00,” “11” or both with discrete bits, including the internal Health Monitor.
  • By increasing to a 12-pin package, all four decoder answers can remain accessible and two additional discrete outputs can be added, including the internal Health Monitor.
2 x 4 ARINC 429 Multi-Bit Converter Block Diagram

3 X 8 Decoder

Three specified ARINC data bits are input to the 3 X 8 decoder producing eight binary results on eight separate output pins. Output polarity for the decoded bits can be specified as Open = True or Ground = True.

Additional Options

  • Within the same 12-pin package, repurpose decoder answer “000,” “111” or both with discrete bits, including the internal Health Monitor.
3 x 8 ARINC 429 Multi-Bit Converter Block Diagram

ARINC 429 Multi-Bit Binary Decoder – Application Examples

To help system designers understand the potential of NEXSYS Component Technology, we have assembled a collection of Application Notes. The links below show example applications that utilize the ARINC 429 Multi-Bit Binary Decoder (SR429/4D) component.

WAAS Approach