Question

An application requires a 3-input AND gate; however, all three of the inputs actually produce a LOW when the inputs are ON. What type of logic gate would lend itself to this application?

1) AND gate
2) OR gate
3) NAND gate
4) XOR gate

Answer 1

The type of logic gate that would lend itself to this application is the NAND gate.

Step-by-step explanation:

A 3-input AND gate requires all of its inputs to be HIGH in order to produce a HIGH output. However, in this application, all three inputs produce a LOW when they are ON. This indicates that we need a gate that produces a HIGH output only when all of its inputs are LOW.

The logic gate that is suitable for this application is the NAND gate. The NAND gate produces a HIGH output when any of its inputs are LOW. Since all three inputs in this case produce a LOW output, the NAND gate will produce a HIGH output.

Example:

A B C Output
0 0 0 1 (LOW)
1 0 0 1 (LOW)
0 1 0 1 (LOW)
1 1 0 1 (HIGH)