D ID 0 D 1D1 D2 ID IY D3 ID D 2D 74153 D D6 2D2 D7 2D3 2EN AIA O A2 AI AO 图42.23(a)四选一扩展为八选一MUX5 1 2 3 4 5 6 A B C D 1 2 3 4 5 6 D C B A Title Size Number Revision B Date: 19-Feb-2002 Sheet of File: C:\Program Files\Design Explorer 99 SE\Library\YangHengXin\MyDesign.ddb Drawn By: 1 Y 2 D 2EN 2 D 2 D 0 1 2 3 0 1 2 D 74153 1 D 1 D 1 D 1 D 2 3 1EN 2 Y A 1 A 0 1 1 D D D D D D D D A A A Y 0 1 2 3 4 5 6 7 2 1 0 图 4.2.23 ( a ) 四选一扩展为八选一MUX