Assignment 1: To verify the Truth Table of Basic Logic Gates
Logic Gates:
- Fundamental building blocks of digital circuits.
- Perform logical operations on one or more binary inputs (0 or 1) and produce a single binary output.
- Essential for decision-making and calculations in computers, calculators, memory devices, and other digital systems.
Basic Gates:
- AND Gate: Outputs 1 only if all inputs are 1.
- OR Gate: Outputs 1 if at least one input is 1.
- NOT Gate: Inverts the input (0 becomes 1, 1 becomes 0).
Truth Tables:
- Tabular representations of the relationship between inputs and outputs of logic gates.
- List all possible input combinations and their corresponding output values.
Truth Tables for Basic Gates:
NOT Gate:
| Input (A) | Output (Y) |
| 0 | 1 |
| 1 | 0 |
AND Gate:
| Input A | Input B | Output (Y) |
| 0 | 0 | 0 |
| 0 | 1 | 0 |
| 1 | 0 | 0 |
| 1 | 1 | 1 |
OR Gate:
| Input A | Input B | Output (Y) |
| 0 | 0 | 0 |
| 0 | 1 | 1 |
| 1 | 0 | 1 |
| 1 | 1 | 1 |
Assignment 2: To verify the Truth Table of Combinational Logic Gates
- XOR Gate: Outputs 1 if the inputs are different.
- XNOR Gate: Outputs 1 if the inputs are the same.
XOR Gate:
| Input A | Input B | Output (Y) |
| 0 | 0 | 0 |
| 0 | 1 | 1 |
| 1 | 0 | 1 |
| 1 | 1 | 0 |
XNOR Gate:
| Input A | Input B | Output (Y) |
| 0 | 0 | 1 |
| 0 | 1 | 0 |
| 1 | 0 | 0 |
| 1 | 1 | 1 |
Assignment 3: To verify the Truth Table of Universal Logic Gates
Universal Gates:
- NAND Gate: Outputs 1 if at least one input is 0.
- NOR Gate: Outputs 1 only if all inputs are 0. (These can be combined to create any other logic gate, hence the name “universal”)
NAND Gate:
| Input A | Input B | Output (Y) |
| 0 | 0 | 1 |
| 0 | 1 | 1 |
| 1 | 0 | 1 |
| 1 | 1 | 0 |
NOR Gate:
| Input A | Input B | Output (Y) |
| 0 | 0 | 1 |
| 0 | 1 | 0 |
| 1 | 0 | 0 |
| 1 | 1 | 0 |
Assignment 4: To verify the Truth Table of Half Adder Combinational Circuit
Understand the Half Adder:
- It’s a tiny circuit that adds two single-digit binary numbers (0 or 1).
- It has two inputs (A and B) and two outputs:
- Sum (S): The result of adding A and B, without any carry-over.
- Carry (C): A 1 if adding A and B resulted in a “carry” to the next digit, otherwise 0.
Know the Truth Table:
| Input A | Input B | Sum (S) | Carry (C) |
| 0 | 0 | 0 | 0 |
| 0 | 1 | 1 | 0 |
| 1 | 0 | 1 | 0 |
| 1 | 1 | 0 | 1 |
Verification Methods:
a. Simulation:
- Use software like Logisim, Multisim, or Tinkercad to create a virtual Half Adder circuit.
- Apply all input combinations (00, 01, 10, 11) and observe the outputs.
- Compare the simulated outputs with the expected truth table to check for accuracy.
b. Physical Circuit:
- If available, build a physical Half Adder using logic gates (e.g., XOR, AND) and ICs (integrated circuits).
- Apply input combinations using switches or probes.
- Measure the output voltages with a multimeter or logic probe.
- Verify if the outputs match the truth table.
