SOLUTIONS FOR DIGITAL DESIGN A QUIZ REVIEW

#1

But this would also be acceptable:

 

 

#2

 

#3

Note that in the image below, one can make the case that I should have made the shorter leg as the negative leg.  (But that’s too much work to change on the computer.)

 

#4

NAND – 7400                    OR – 7432
NOR – 7402                       XOR – 7486
NOT – 7404                        555 Timer – 555
AND – 7408

#5

<ASK MR. CAMPEAU IF YOU NEED HELP>

 

#6

<ASK MR. CAMPEAU IF YOU NEED HELP>

 

#7

Note that you do NOT need to know the equivalent circuit.  This would be provided to you.

<ASK MR. CAMPEAU IF YOU NEED HELP>

 

#8

-Not powered or not grounded
-Burnt
-Connect backwards
-Connected in wrong breadboard hole

#9

Breadboard allow for very easy connections to be made between devices.  Breadboards also keep the different components steady and organized.  Imagine trying to connect everything using alligator clips!  Yikes!  Every project would end up as a massive pile of “stuff”.

 

#10
In a combinational circuit, the outputs are entirely reliant on the current combination of the inputs.

In a sequential circuit, the outputs are reliant on the current inputs but also on the circuit’s previous state(s) as there is feedback into the circuit.

#11

A pinout is a diagram that provides us with the functionality of each pin of an IC.

<See Mr. Campeau if you need help providing an example.>

Pinouts can easily be found on the internet.  Use Google!  The manufacturer of the component also provides a pinout on the site.

 

#12                                                                                                                                     

Truth table

A             B             Co          S
0             0             0             0
0             1             0             1
1             0             0             1
1             1             1             0

 

Circuits:
A AND B = Co
A XOR B = S

<See Mr. Campeau ifyou need help drawing the above circuits on the breadboard.>

 

#13

<This question requires that you know the equivalent circuit for XNOR.  This will not be asked on the test.  Though it is certainly reasonable to do as review.>

<Ask Mr Campeau if you need help.>

 

#14

<Ask Mr. Campeau if you need help.>

Note that you should know what a decoder is and should be able to recreate a circuit diagram for it.  This is a fair question for the test.  However, it would be very messy to mark for me.

 

#15

a-F
b-F
c-F (TTL = Transistor Transistor Logic)
d-T
e-F
f-T
g-T
h-T
i-T
j-T
k-T

 

#16

a-decoder
b-24 = 16
c-positive
d-resistors
e-half adder
f-full adder
g-2, 2
h-4
i-parity checker
j-0  (as there is an even number of 1s)
k-decoder
l-demultiplexer
m-pinout

 

#17

For a multiplexer, the value of A & B determine which input line is connected to the output.  If AB are 00, the input 00 is connected to the output.  If AB are 01, then input 01 is connected to the output.  And so on…

 

#18

AB is 10 so input line 10 (C2) is connected to the output.  Since C2 has a value of 1, the output will have a value of 1.