Lab 6
OBJECTIVES:
To learn and understand the working of different types of decoders
To learn and understand how to design a multiple output combinational
circuit using Decoders
EQUIPMENT : Logic trainer, Logic probe
COMPONENTS:ICs 74LS08, 74LS32, 74LS04, 74LS139
2-to-4 line decoders:
74LS139 IC contains two fully independent 2-to-4 line decoders with active low enables. The
function table and connection diagram for this IC are shown below:
Function Table:
Enable Selection Inputs Outputs
G B A Y0 Y1 Y2 Y3
H X X H H H H
L L L L H H H
L L H H L H H
L H L H H L H
L H H H H H L
H= Logic High, L= Logic Low, X= Don’t Care
Connection Diagram:
