Boolean Algebra

Example: NEGATIVE & POSITIVE LOGIC

Q- We are given a circuit as follow:

Identify the above circuit as an AND or OR gate. Explain using negative and positive logic.

Ans:  We assume the voltage levels of +5V & 0V. So if we give both inputs as 0V then output would be 0V too. Similarly we obtain other cases as given in the table below:

This is the truth table for AND gate.

Hence we can the circuit given would act as AND gate in NEGATIVE LOGIC while as OR gate in POSITIVE LOGIC