View tc74hc139p datasheet:

TC74HC139P IL08 C-MOS DUAL 2-TO-4 DECODER/DEMULTIPLEXER —TOP VIEW— 4 12 Y0 Y0 IN 1 VDD 16 5 14 11 2 1EN A Y1 A Y1 3 6 13 10 B Y2 B Y2 1A IN 2 15 IN 79 2EN Y3 Y3 EN EN 1B IN 3 14 2A IN 115 OUT 4 13 2B IN 1Y0 INPUTS OUTPUTS OUT 5 12 OUT EN B A Y3 Y2 Y1 Y0 1Y1 2Y0 0 0 0 1 1 1 0 OUT 6 11 OUT 0 0 1 1 1 0 1 1Y2 2Y1 0 1 0 1 0 1 1 OUT 7 10 OUT 0 1 1 0 1 1 1 1Y3 2Y2 1 x x 1 1 1 1 8 GND 9 OUT 2Y3 0 : LOW LEVEL 1 : HIGH LEVEL x : DON’T CARE