Shared transient voltage suppressor having built-in-test capability for solid state power controllers

A method of forming a lightning protection circuit configured for use in a solid state power controller (SSPC) comprising at least one feed line and a plurality of load lines, the method comprising:

• providing a power metal oxide semiconductor field effect transistor (MOSFET) communicatively coupled to the at least one feed line and at least one of the plurality of load lines, wherein the power MOSFET is configured to switch voltage on the feed line into and out of the at least one of the plurality of load lines;
• providing a shared transient voltage suppressor communicatively coupled between a positive clamp rail and a negative clamp rail;
• providing a transient isolator;
• communicatively coupling the transient isolator to the shared transient voltage suppressor;
• configuring the transient isolator to be communicatively coupled to by the at least one feed line and the plurality of load lines;
• and
• communicatively coupling the transient isolator to the at least one feed line and the plurality of load lines, such that, when the power MOSFET is off while energy above a breakdown voltage of the power MOSFET is on the at least one feed line or the at least one of the plurality of feed lines, the energy above the breakdown voltage on any one of the at least one feed line and the plurality of load lines is dissipated in the following manner:
• if the energy above the breakdown voltage comprises energy of a positive transient pulse on the one load line, the energy of the positive transient pulse is dissipated through the following path:
• through the a first diode of the transient isolator to the positive clamp rail;
• through the positive clamp rail to the shared transient voltage suppressor;
• through the shared transient voltage compressor to the negative clamp rail;
• through the negative clamp rail to a second diode of the transient isolator;
• and
• through the second diode to the ground.

A lightning protection circuit configured for use in a solid state power controller (SSPC) comprising at least one feed line and a plurality of load lines, the lightning protection circuit comprising:

• a power metal oxide semiconductor field effect transistor (MOSFET) communicatively coupled to the at least one feed line and at least one of the plurality of load lines, wherein the power MOSFET is configured to switch voltage on the feed line into and out of the at least one of the plurality of load lines;
• a shared transient voltage suppressor communicatively coupled between;
• and
• a transient isolator communicatively coupled to the shared transient voltage suppressor;
• wherein the transient isolator is configured to be communicatively coupled to the positive clamp rail, the negative claim rail, the at least one feed line, and the plurality of load lines;
• wherein, when the transient isolator is communicatively coupled to and shared by the at least one feed line and the plurality of load lines, and when the power MOSFET is off while energy above a breakdown voltage of the power MOSFET is on the at least one feed line or the at least one of the plurality of feed lines, the energy above the breakdown voltage on any one of the at least one feed line and the plurality of load lines is dissipated through the shared transient voltage suppressor.