Question

A full adder logic circuit will have __________

(a) Two inputs and one output

(b) Three inputs and three outputs

(c) Two inputs and two outputs

(d) Three inputs and two outputs

I got this question in a national level competition.

This interesting question is from Logic Gates and Networks topic in section Boolean Algebra and Minimization Techniques and Logic Gates of Digital Circuits

Answer 1

The correct answer is (d) Three inputs and two outputs

For explanation: A full adder circuit will add two bits and it will also accounts the carry input generated in the previous stage. Thus three inputs and two outputs (Sum and Carry) are there. In case of half adder circuit, there are only two inputs bits and two outputs (SUM and CARRY).