Start with a black image, make sure your background colour is set to a colour (not important which colour) before going to the next step, will not work with white
Apply the stylize/tiles filter at 10tiles, 10%max offset and background colour as the fill
Now apply the stylize/glowing edges filter with these settings, w2, b6, s5
Apply hue/saturation with colorize ticked with these settings, h124, s50, L+36
Now apply the lighting effects filter on default, no texture channel, so it looks like this. Thats the base circuit done.
I just painted some bits and bobs on a new layer to finish it off, experiment with it, looks nice shrunk down and used in interfaces, grab the action on my actions page.

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