Question

What is realisation of logic gates?????

Answer 1

Realization is the process of making different gates using the combination of given gates or diodes.

Example.

Realisation of an OR gate using diodes 1. When both A and B are earthed (i.e. connected to low input 0), both the diodes do not conduct and no voltage develops across R. Therefore the voltage at C is zero with respect to earth. Hence the output Y is 0 (in levels). 2. When A = 0 and B = 1 (i.e., connected to positive terminal), the diode D2 conducts but D1 does not. Since D2 is ideal, no voltage drop takes place across D2 and a full voltage drop of 5V takes place across R at C, +5V with respect to earth. Therefore Y is 1 (in level). 3. When A = 1 and B = 0, D1 conducts but D2 does not. For the same reason as stated above the output Y is 1 (in level). 4. When A = 1 and B = 1, both diodes conducts since the diodes are ideal and connected in parallel, the voltage drop across R cannot exceed 5V, with C at +5V with respect to earth. Hence the output Y will be 1 (in level). The truth table of OR gate A B C 0 0 0 0 1 1 1 0 1 1 1 1