Lorenzo C. Caballa
ENGG 121.02
Circuit Diagram:
COMBINATIONAL
Introduction:
Boolean
functions
can
be
minimized using the different theorems,
postulates, or graphical solutions to result
in simpler circuit diagrams. This laboratory
exercise aims to give the student the ability
and knowledge to design combinational
digital circuits given a set of specifications.
Part One: 3-Bit Majority 1 Ckt
Implement the truth table given below.
A
B
C
OUT
0
0
0
0
0
0
1
0
0
1
0
0
0
1
1
1
1
0
0
0
1
0
1
1
1
1
0
1
1
1
1
1
Results and Discussion:
K-MAP
BC
A
1
1
1
Simplified Expression:
OUT = AB + BC + AC
1
https://www.multisim.com/content/MhbhN6wQa8Avn5
AcZam2Hf/circuit-21-caballa/open/
Upon observing the truth table, A K-map
was constructed given the table’s
specification and an expression for the Kmap was created. Using the expression, the
circuit diagram was constructed with
multism using only AND and OR gates.
Part Two: House Alarm
Circuit Diagram:
Results and Discussion:
House Alarm Truth Table
E
D
W
A
0
0
0
0
0
0
1
0
0
1
0
0
0
1
1
0
1
0
0
1
1
0
1
1
1
1
0
1
1
1
1
0
K-MAP
DW
E
1
1
Simplified Expression:
A = EW’+ED’
1
A truth table was first filled given the
specifications with variables E, W, D, and
A. Like activity 1, a K-map was utilized to
obtain the expression required to create a
circuit. This time, Electronic workbench
was used to utilize the ICs 7404, 7408, and
7432 which are the NOT, AND, and OR
gates respectively. The output obtained was
equivalent to that of the variable A in the
truth table.
Part Three: Basic Combinational
YZ
A.
Implement the truth table given below.
W
X
Y
Z
F
0
0
0
0
0
0
0
0
1
0
0
0
1
0
1
0
0
1
1
0
0
1
0
0
0
0
1
0
1
0
0
1
1
0
1
0
1
1
1
1
1
0
0
0
1
1
0
0
1
1
1
0
1
0
1
1
0
1
1
1
1
1
0
0
0
1
1
0
1
0
1
1
1
0
1
1
1
1
1
1
WX
1
1
1
Simplified Expression:
X = WX’ +YZ’ + XY
1
1
1
1
1
1
B.
YZ
Implement the truth table given below.
W
X
Y
Z
F
0
0
0
0
1
0
0
0
1
0
0
0
1
0
1
0
0
1
1
0
0
1
0
0
0
0
1
0
1
1
0
1
1
0
0
0
1
1
1
1
1
0
0
0
1
1
0
0
1
0
1
0
1
0
1
1
0
1
1
1
1
1
0
0
0
1
1
0
1
1
1
1
1
0
1
1
1
1
1
1
WX
1
1
1
1
1
1
1
1
1
1
Simplified Expression:
X = X’Z’ +XZ + WY
For both parts of activity 3, K-maps were
made given the using the respective truth
tables and an expression for the truth tables
were obtained. After which, the circuit
diagram was constructed with Electronics
Workbench using 7404, 7408, and 7432
IC’s for part 1 and thee 7400s and a 7410
for part 2. The respective truth table was
achieved for both parts.
Conclusion:
The student, through combinational
techniques, was able to implement the
given specifications into a circuit by
utilizing logic gates and integrated circuits.
Index:
Oppus, C. (2008), Digital Design System &
Switching Theory Lab Manual, 4th Edition,
Laboratory Exercise 1&2.