DNT 231 DIGITAL SYSTEM 1
Laboratory Manual
LAB 3: KARNAUGH MAPPING TECHNIQUE
OBJECTIVES
1. To design a combinational logic circuit with simplest logic gates representation
using Karnaugh Mapping Technique.
EQUIPMENTS/COMPONENTS
• A DC power supply capable of 5V DC output
• A multimeter
• Logic Gate IC : 7400(2 pc), 7404 (1pc), 7432 (1pc), 7408 (1pc)
• Light Emitting Diode (1pc)
• Resistors : 330Ω (1pc)
• Switches (3pc)
INTRODUCTION
Karnaugh Maps
Karnaugh Map provides a systematic method for simplifying Boolean expressions. Using
K-Map is very similar to truth table. K-Map can be used for expressions with two, three,
four or five variables.
Number of cells in a K-Map is equivalent to the number of possible input variable
n
combinations (2 ). As an example:
3
For 3-variables; number of cells are 2 = 8
The cells in K-Map are arranged so that only one single variable changes between
adjacent cells.
In the experiment, you will be given a design problem. You should be able to interpret
the design problem into a truth table and apply the Karnaugh Map technique to find the
simplest logic expression. Finally, you have to construct and test the circuit.
________________________________________________________________________
UNIVERSITI MALAYSIA PERLIS
by Pn.NUR ADYANI bt MOHD AFFENDI
DNT 231 DIGITAL SYSTEM 1
Laboratory Manual
PROCEDURE
Design Problem using Karnaugh Mapping Technique
A jet aircraft employs a system for monitoring the rpm, pressure, and temperature values
of its engines using sensors that operate as follows:
 RPM sensor output = 0, only when speed < 4800 rpm
 P sensor output = 0, when pressure <220 psi
 T sensor output = 0, only when temperature < 200˚F
Figure 1.1 shows the logic circuit that controls a cockpit warning light for certain
combinations of engine conditions. Assume that a HIGH at output W activates the
warning light:
(a)
(b)
(c)
(d)
Create your truth Table with appropriate input-output combinations
Determine what engine conditions will give warning to the pilot.
Using K-Map technique to obtain your simplified Boolean equation.
Change this circuit to one using all NAND gates and constructs the circuit.
Figure 1.1
REPORT REQUIREMENT
The lab report should include the following:
1. Summary of experiment done.
2. Results of experiment.
3. Discussions on K-map :include your K-Map table, the simplified Boolean
equation, the circuit diagram, the truth table and the engine conditions.
4. Remarks on any possible failures and measures done to overcome this problem.
5. Conclusion for the experiments.
_______________________________________________________________________
UNIVERSITI MALAYSIA PERLIS
by Pn.NUR ADYANI bt MOHD AFFENDI
DNT 231 DIGITAL SYSTEM 1
Laboratory Manual
DNT 231 DIGITAL SYSTEM I
EXPERIMENT DATA SHEET
NAME :____________________________________
METRIC NO.:____________
COURSE :___________________________________________
LAB EXPERIMENT : _________________________________
Karnaugh Map Design Method
(a)
INPUTS
OUTPUT
Truth Table
(b) The engine conditions that will give warning to the pilot:
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UNIVERSITI MALAYSIA PERLIS
by Pn.NUR ADYANI bt MOHD AFFENDI
DNT 231 DIGITAL SYSTEM 1
Laboratory Manual
(c) K-Mapping :
Simplified Boolean equation:
(d) Logic Circuit Diagram using all NAND gates
______________________________________________________________________________________
UNIVERSITI MALAYSIA PERLIS
by Pn.NUR ADYANI bt MOHD AFFENDI
INSTRUCTOR’S SIGNATURE: ________________________________