View the complete Teaching Digital Logic Fundamentals tutorial series
As part of any digital logic fundamentals course, it is important that students learn the importance and process of logic simplification. Finding equivalent circuits that can be achieved with fewer components can often reduce manufacturing costs and improve reliability.
This tutorial will provide an example of how Multisim can help students understand the process of logic simplification. Multisim allows students to work through the process of applying the theory, creating a logic diagram, understanding and simplifying the response, all while demonstrating these skills using hardware.
In this tutorial we are going to work on the simplification of the logic diagram below. Currently, this contains a series of NOT gates and NOR gates. In simplifying this diagram we want to reduce the overall number of logic gates.
Before attempting to simulate this circuit, the student should try to apply theory to derive the Boolean expression for the circuit and use Boolean algebra to attempt to simplify it. Multisim allows students to check their thought processes and produce verified results.
From the truth table we can see that the output is high when input A is high and input C is low.
A’B’C + A’BC
A’C
Still using the Logic Converter, we can use this expression to generate a logic diagram. To do this click the conversion highlighted below.
This will generate a simple AND gate with one of the inputs inverted through a NOT gate.
Once the simplification of the logic diagram is complete, we can deploy this to the hardware.
Use the switches and LEDs denoted in the schematic to confirm that the hardware response is identical for the original and the simplified circuit.
This tutorial demonstrates how, by using the intuitive tools within Multisim and the Digilent educational teaching boards, students can take a hands-on approach to learn digital logic simplification.