DIT 079 DIGITAL ELECTRONICS

 DIT 079 DIGITAL ELECTRONICS

QUESTION ONE (24 MARKS)

    a)    Categorize the different ways of representing numerical values of quantities                                                                                                       (2 marks)

    b)    Define the term digital quantity hence state an example.         (3 marks)

    c)     Name the different number systems used in digital technology.                                                                                                                                            (4marks)

    d)    Outline the different basic logic gates.                                              (3 marks)

    e)    Utilizing Boolean algebra, solve the following Boolean expression

F = C(B + C)(A + B + C)                                                                                    (5 marks)

    f)      Differentiate between a latch and a flip flop.                                  (2 marks)

    g)    Distinguish between Minterms and Maxterms                             (2 marks)

    h)   List the main categories of sequential circuits.                              (3 marks)

QUESTION TWO (18 MARKS)

    a)    Define the term universal gates.                                                         (2 marks)

    b)    List two universal gates.                                                                         (2 marks)

    c)     Draw a NOR gate and its truth table                                                  (3 marks)

    d)    Outline the De Morgan’s theorems hence prove them using truth table method.                                                                                                           (6 marks)

    e)    Apply De Morgan’s theorem to equate A(B + C)                          (2 marks)

    f)      Create a logic circuit using NAND gates only for the expression

X = A (B + C)                                                                                             (3 marks)

 

QUESTION THREE (18 MARKS)

    a)    What is a shift register?                                                                         (2 marks)

    b)    Outline the basic types of registers.                                                   (4 marks)

    c)     State three applications of shift registers.                                       (3 marks)

    d)    List the different types of counters and briefly explain how each of them works                                                                                                             (9 marks)                        

 

 

QUESTION FOUR (18 MARKS)

    a)    Contrast between combinational logic circuits and sequential logic circuits clearly stating all the differences with respect to their output, memory and fundamental building block.                                                (6 marks)

    b)    Design a JK flip flop using a D flip flop.                                         (12 marks)

 

QUESTION FIVE (18 MARKS)

    a)    With the help of a diagram, explain hence illustrate what you understand by the term “Don’t care terms”.                                  (4 marks)

    b)    State five main reasons for simplifying Boolean functions.      (5 marks)

    c)     Contrast between a standard Sum Of Products (SOP) and a standard Product Of Sums with respect to digital electronics.                  (2 marks)

    d)     

            i.      What is the function of a Karnaugh map.                (2 marks)

            ii.      State the various kinds of Karnaugh maps                    (3 marks)

 

    e)    Outline two different techniques used for simplifying boolean equations (2 marks)