Techniques to Design Robust Lightning Protection Circuits for Avionics Equipment

This chapter presents techniques for the design of robust lightning protection circuits for electronic equipment on aircraft/avionics. The first step in designing a protection circuit is to determine the transient against which the circuit will be protecting. This is usually provided during requirements capture. Transient voltage suppressors (TVS), metal oxide varistors (MOV), or gas discharge tubes (GDT) are common voltage‐clamping devices. The voltage‐clamping device adjusts the current to maintain a constant voltage. An MOV is a passive, nonlinear solid state device designed to vary its resistance in response to the applied voltage. The outputs of the design tool used for TVS selection are: TVS pulse width and TVS peak power. GDTs are excellent voltage‐clamping devices in that they can tolerate a large amount of current clamping the voltage applied to the downstream components to a very low value.