Question

What are 7 symbols to represent logic gates?

Answer 1

In digital electronics, **logic gates** are fundamental building blocks that perform logical operations based on binary inputs. These operations are typically visualized using distinct symbols that represent each gate. Here are the **7 primary symbols** for logic gates:

1. **AND Gate**:
   - **Symbol**: A flat-ended shape (a "D"-like shape) with two or more input lines on the left and one output line on the right.
   - **Function**: It gives a high output (1) only when all its inputs are high (1).
   - **Truth Table**: Output = 1 if both inputs are 1; otherwise, 0.

2. **OR Gate**:
   - **Symbol**: A curved shape with two or more input lines and one output line.
   - **Function**: It gives a high output (1) if at least one input is high (1).
   - **Truth Table**: Output = 1 if one or more inputs are 1.

3. **NOT Gate (Inverter)**:
   - **Symbol**: A triangle with a small circle (representing inversion) at the tip.
   - **Function**: It outputs the opposite of the input (inverts the signal).
   - **Truth Table**: Output = 1 if input is 0, and vice versa.

4. **NAND Gate**:
   - **Symbol**: Same as the AND gate but with a small circle (inversion) at the output.
   - **Function**: It gives a low output (0) only when all inputs are high (1); otherwise, it gives a high output.
   - **Truth Table**: Output = 0 only if all inputs are 1.

5. **NOR Gate**:
   - **Symbol**: Same as the OR gate but with a small circle at the output.
   - **Function**: It outputs a low (0) unless all inputs are low (0); otherwise, it produces a high output.
   - **Truth Table**: Output = 1 only if all inputs are 0.

6. **XOR Gate (Exclusive OR)**:
   - **Symbol**: An OR gate symbol with an additional curved line on the input side.
   - **Function**: It outputs a high (1) if the number of high inputs is odd.
   - **Truth Table**: Output = 1 if the inputs are different (one high and one low).

7. **XNOR Gate (Exclusive NOR)**:
   - **Symbol**: Same as the XOR gate symbol but with a small circle at the output.
   - **Function**: It outputs a high (1) if the number of high inputs is even (i.e., both inputs are equal).
   - **Truth Table**: Output = 1 if both inputs are the same.

These symbols are widely used in circuit diagrams to represent the basic logical operations and help simplify complex digital circuits.