Application Notes

A Main Entry Door (MED) Switch is used to “lock out” the door close function. When the MED SAFETY switch is engaged, power to the DOOR CLOSE switch is interrupted, disabling the DOOR CLOSE switch. In order to save power, the MED SAFETY switch only illuminates for 10 seconds when selected and for 10 seconds anytime the DOOR CLOSE switch is depressed while the MED SAFETY switch is engaged.

This application details an aircraft SPEAKER MUTE function used to silence redundant or repetitive aural messages in the cockpit. Separate mute switches are provided for the pilot and the co-pilot and the mute function may be selected or canceled by either. The mute function may also be automatically canceled if a defined emergency condition exists such as activating supplemental oxygen or Master Warning.

In-Flight Entertainment (IFE) systems require custom control hardware to activate or switch between different audio sources. NEXSYS Component Technology offers a simple solution to this challenge with the ability to isolate and buffer individual signals and control multiple individual modes. This application example switches between BLU-RAY, AUX and XM Satellite Radio.

Switch functions may be dependent upon different conditional inputs. As an example, certain aircraft systems should be active only when mission power is available or safety concerns can limit systems to being active only when the aircraft is weight off wheels. This application example demonstrates a circuit that requires three conditions to be in a defined state before power to a specified function is active.

This application presents a three state warning control that provides an off, blink or steady-state condition. The warning control advises of an alarm condition that can be acknowledged and reset to steady state without canceling the original warning signal. The warning unit also initiates and drives an accompanying aural alarm that is muted when the switch is pressed.