Semiconductor footprint names shall be A B C:

• A = IPC name e.g. SOIC, TSOPI, TSOPII, TSSOP, QFP, SOJ, BGA, add ‘–EP’ for exposed pad components.
• B =
  • Pin count e.g. 16PIN
  • For BGA use BGA <pins>C<pitch>P<columns>X<rows>
  • For QFP use QFP <pitch>P<length>X<width>X<pins>C
  • For SOJ use SOJ <pitch>P<length>X<width>X<pins>C
• C = density
  • SD
  • HD