1-to-4 Demultiplexer

In a digital circuit, a demultiplexer (or demux) is a combinational logic circuit that takes a single input and selects one of many possible outputs based on the value of select lines. A 1-to-4 demultiplexer has one input line and four output lines.

Select Lines

The select lines in a demultiplexer determine which output line is selected. In a 1-to-4 demultiplexer, the number of select lines required can be calculated using the formula 2^n = m, where n is the number of select lines and m is the number of output lines.

In this case, we have 4 output lines. Therefore, to find the number of select lines required, we need to solve the equation 2^n = 4.

Solving for n

To find the value of n, we can use trial and error. Starting with n = 1, we can substitute the value of n into the equation and check if 2^n equals 4.

- For n = 1, 2^1 = 2 (not equal to 4)
- For n = 2, 2^2 = 4 (equal to 4)

Therefore, the number of select lines required for a 1-to-4 demultiplexer is 2 (option A).

Explanation

A 1-to-4 demultiplexer has one input line and four output lines. The select lines determine which output line is selected. The number of select lines required can be found using the formula 2^n = m, where n is the number of select lines and m is the number of output lines.

In this case, we have 4 output lines. By solving the equation 2^n = 4, we find that n = 2. Therefore, 2 select lines are required for a 1-to-4 demultiplexer.