2 layers66.4 × 90.9 mm

Boards in 1 GitHub repository, designed in KiCad, that use the BD09AV by C&K (-40℃~+85℃ 100mA 2.54mm 5V 9 PC Pin Red SPST Slide, Rocked 插件,P=2.54mm DIP Switches ROHS). See how each wires it, with its parts, size, README and files; the BD09AV’s symbol, footprint and pinout are on its own page.
