+---+--+---+ +---+---*---+ __ 1A |1 +--+ 14| VCC | A | B |/Y | /Y = AB 1B |2 13| 4B +===+===*===+ /1Y |3 12| 4A | 0 | 0 | Z | 2A |4 7438 11| /4Y | 0 | 1 | Z | 2B |5 10| 3B | 1 | 0 | Z | /2Y |6 9| 3A | 1 | 1 | 0 | GND |7 8| /3Y +---+---*---+ +----------+