3.2.2.4 Switch symbols

General switch symbol names shall be SW A B C D E F where:

  • A = Generic name (see below) or manufacturer e.g. BULGIN
  • B = Generic build (see below) or family e.g. MPI
  • C = optional configuration for variations
  • D = optional additional information such as TH or SM for variations
  • E = optional SPLIT if a split switch model


Generic name

  • 1A = SPST (NO) (xA for multiple)
  • 1B = SPST (NC) (xB for multiple)
  • 2A = DPST (NO)
  • 2B = DPST (NC)
  • 1A1B = DPST (NO & NC)
  • 1C = SPDT
  • 2C = DPDT


Generic build DPDT abcdefgh<space>i(j etc)

  • a = NO 1 pin number
  • b = COM 1 pin number
  • c = NC 1 pin number
  • d = NO 2 pin number
  • e = COM 2 pin number
  • f = NC 2 pin number
  • g = GND or Screen pin number(s)