Logic Gates
Logic Gates: Overview
This topic covers concepts such as Types of Signals, Analogue Signals, Digital Signals, Logic Gates, Truth Table in Logic Gates, The NOT Gate, The OR Gate, The AND Gate, The NAND Gate, The NOR Gate, and The XOR Gate.
Important Questions on Logic Gates
The same input signal is applied to both the (input) terminals of a given logic gate.
If the output is the(i) same as the (common) input signal
(ii) inverted with respect to the (common) input signal,
Identify the logic gate/s involved in each case.

Write down the output at for the inputs and

Identify the logic gates marked and in the given logic circuit.

Identify the logic gates marked P and Q in the given logic circuit.

(i) Identify the logic gates marked P and Q in the given logic circuit.

The inputs A and B are inverted by using two NOT gates and their outputs are fed to the NOR gate as shown below.
Analyse the action of the gates (1) and (2) and identify the logic gate of the complete circuit so obtained.

Which of the following flip-flops does not have race problem?

The truth table of a certain logic circuit is shown below.
(input) | (input) | (output) |
The logic gate represented by the above truth table belongs to







Digital signals have ________ noise immunity compared to the analog signals.


In the given circuit, the input voltages at and could be either or . Use the fact that a diode under forward bias is a short circuit, and under reverse bias is an open circuit. The truth table of the circuit will be that of

Identify the gate and match in the bracket to check.

The combinations of gates shown here (in the figure) are equivalent to

If are inputs to a gate and is its output, then, as per the following time graph, the gate is:
