74138 Demultiplexer IC

Functionality: The 74138 is a 3-to-8 line demultiplexer. It has three binary input lines (A, B, and C) and eight output lines (Y0 to Y7). These input lines select one of the eight output lines to which the input data is directed.

Input Selection: The three input lines (A, B, and C) allow for a total of 2^3 = 8 different binary combinations (000 to 111). Each combination selects one of the eight output lines. For example, if the input is 010 (binary), it will enable output Y2 while keeping all other outputs inactive.

Enable Inputs: The 74138 also features two active low enable inputs, G1 and G2A/G2B. These inputs control the operation of the demultiplexer. When G1 is low, the demultiplexer is enabled. G2A and G2B inputs allow for cascading multiple 74138 ICs to increase the number of output lines.

Note: The 74138 IC is commonly used in digital circuits for tasks such as memory address decoding, input selection, and routing data to different output lines based on specific conditions. Its versatility makes it a valuable component in digital system design.