Assessment 3 Digital Electronics
Student Name _____________________________________
Multiple Choice
1.
What is 1101 1010 as a base 10 number?
a.
b.
c.
d.
2.
What is 1101 1010 as a base 16 number?
a.
b.
c.
d.
3.
f1
ac
da
85
What is the purpose of simplifying an expression?
a.
b.
c.
d.
4.
218
208
228
210
To make more work
To make it easier to test
To ensure the simplest possible circuit
To gain more math skills
What is the simplified form of the following expression?
ABC  ABC  ABC  ABC  ABC
c.
A  ABC
AB  AB  ABC
A( B  B )  ABC
d.
AC  AC  ABC
a.
b.
5.
Which one of the following properly uses DeMorgan’s Theorem for the following expression in
its unsimplified form?
( ABC )  (CB)
b.
ABC  C  B
( A BC )  C B
c.
( ABC )(C  B)
d.
( A  B  C )(C  B)
a.
Constructed Response
1.
What is the purpose of using a hex numbering system for digital storage? Provide a mathematical
example of your justification.
2.
Complete a truth table and diagram the following Boolean Expression:
ABC  ABD  AC D  AC  AB
3.
Can the expression above be simplified? If so simplify the expression below, if not state the
reasons why it cannot be simplified.
4.
How can simplifying an expression help the end product?
5.
Use the following number to solve the statements below
128, 357
Write it as a BCD
Write it in Base 2 (binary)
Write it in Base 16 (hex)
Write it in Base 10 (Decimal)
6. Prove DeMorgan’s Theorem by writing the statements and completing the truth tables for each
expression showing that they are actually the same.
Digital Electronics
Name_______________________________________________
Hour_______________
You have to create a security system for a bank. They want to be able to only allow one person in or out of
the vault room at any time. There are two sets of doors set 15 feet apart. The electronic circuit will only
allow any of the doors to be unlocked if both are closed and the correct code is placed into the key pad
located outside the vault room or general manager overrides the system in the event of an emergency from
a switch located in his office. The magnetic switches used on the door will trigger a high when they are
closed and a low signal when they are open. Additionally a secondary circuit needs to be developed If the
security measures are bypassed. If the sensors read that both doors are forced open, the safety trigger will
activate a flood of chemical gasses into the vault room. Remember we do not want the chemicals to be
distributed if the manager overrides the system and all the doors are unlocked. Your task is to design a
circuit that will provide the logic for this operation. You must provide a detailed sketch of the circuit, the
Boolean expression for each circuit as well as the truth table for it’s operation.