NEETPhysicsSemiconductors
Which of the following logic circuit configurations is equivalent to a NAND gate?
Options
- AInputs A and B are first passed through NOT gates, and their outputs are fed to an AND gate.
- BInputs A and B are first passed through NOT gates, and their outputs are fed to an OR gate.
- CInputs A and B are passed through an OR gate, and its output is fed to a NOT gate.
- DInputs A and B are passed through an AND gate, and its output is fed to an OR gate whose other input is at log
Correct answer
B. Inputs A and B are first passed through NOT gates, and their outputs are fed to an OR gate.
Step-by-step solution
To find the circuit equivalent to a NAND gate, we need to find the configuration that produces the Boolean expression Y = A B . According to De Morgan's theorem: A B = A + B Let us evaluate the given options: Option 1: Inputs are inverted and fed to an AND gate. Output Y = A B = A + B (NOR gate). Option 2: Inputs are inverted and fed to an OR gate. Output Y = A + B = A B (NAND gate). Option 3: Inputs are fed to an OR gate, then inverted. Output Y = A + B (NOR gate). Option 4: Inputs are fed to an AND gate, then to