# Electrical Technology Grade 12 NSC June 2024 QP (Eng)

> Grade 12 Electrical Technology question paper from the NSC June Exam 2024 (English), 31 pages. Read online or download the free PDF.

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- Updated: 2026-09-28
- Subject: Electrical Technology
- Grade: Grade 12
- Language: English
- Document type: Question paper
- Year: 2024
- Exam period: NSC June Exam
- Curriculum: CAPS
- Pages: 31

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## About this document

Electrical Technology · Grade 12 · NSC June Exam · 2024 · English. Question paper, 31 pages. Read online or download the PDF.

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Confidential

             SENIOR CERTIFICATE EXAMINATIONS/
         NATIONAL SENIOR CERTIFICATE EXAMINATIONS

        ELECTRICAL TECHNOLOGY: DIGITAL ELECTRONICS

                                 MAY/JUNE 2024

                                                                       MARKS: 200

                                                                      TIME: 3 hours

           This question paper consists of 22 pages, a 1-page formula sheet
                            and an 8-page answer sheet.

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INSTRUCTIONS AND INFORMATION

1.         This question paper consists of SIX questions.

2.         Answer ALL the questions.

3.         Answer the following questions on the attached ANSWER SHEETS:

           QUESTIONS 3.3.3, 3.5.3 and 3.7.1
           QUESTIONS 5.3, 5.4, 5.6, 5.7.1, 5.7.2, 5.8.1 and 5.10
           QUESTIONS 6.9.2

4.         Write your centre number and examination number on every ANSWER
           SHEET and hand them in with your ANSWER BOOK, whether you have used
           them or not.

5.         Sketches and diagrams must be large, neat and FULLY LABELLED.

6.         Show ALL calculations and round off answers correctly to TWO decimal
           places.

7.         Number the answers correctly according to the numbering system used in this
           question paper.

8.         You may use a non-programmable calculator.

9.         Calculations must include:

           9.1       Formulae and manipulations where needed

           9.2       Correct replacement of values

           9.3       Correct answer and relevant units where applicable

10.        A formula sheet is attached at the end of this question paper.

11.        Write neatly and legibly.

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    QUESTION 1: MULTIPLE-CHOICE QUESTIONS

    Various options are provided as possible answers to the following questions. Choose
    the answer and write only the letter (A–D) next to the question numbers (1.1 to 1.15) in
    the ANSWER BOOK, e.g. 1.16 D.

    1.1        A burn must be treated by …

               A       covering the burnt area with butter.
               B       putting ice on the burn wound.
               C       puncturing the blisters.
               D       running cold water over the burnt area until the pain reduces.                  (1)

    1.2        In an op-amp bistable multivibrator circuit the op amp operates as a/an …

               A       comparator.
               B       summing amplifier.
               C       differentiator.
               D       integrator.                                                                     (1)

    1.3        A/An … changes its output state when a trigger pulse is received. It remains
               in that state for a time determined by the RC time constant. Thereafter it
               returns to its original state.

               A       astable multivibrator
               B       bistable multivibrator
               C       monostable multivibrator
               D       relaxation oscillator                                                           (1)

    1.4        A circuit used to change a sine wave into a square wave with the same
               frequency is a …

               A       comparator.
               B       Schmitt trigger.
               C       monostable multivibrator.
               D       op-amp differentiator.                                                          (1)

    1.5        When a positive square wave is applied to the inverting input of an op-amp
               integrator and the non-inverting input is connected to ground, the capacitor
               will …

               A       charge exponentially to the supply voltage.
               B       discharge exponentially to 0 V.
               C       charge at a constant fixed rate to the negative saturation voltage.
               D       discharge at a constant fixed rate to 0 V.                                      (1)

    1.6        The 555 IC functions as a … in an astable mode operation.

               A       voltage regulator
               B       frequency divider
               C       free running oscillator
               D       None of the above-mentioned                                                     (1)

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    1.7        The main characteristics of operational amplifiers are …

               A       very high output impedance, low input impedance, high voltage gain
                       and wide bandwidth.
               B       low voltage gain, low current gain, low output impedance and narrow
                       bandwidth.
               C       very high voltage gain, high current gain, low output impedance and
                       high input impedance.
               D       very high voltage gain, high input impedance, low output impedance
                       and wide bandwidth.                                                              (1)

    1.8        A … output connects the transistor collector to the LED cathode.

               A       sourcing
               B       draining
               C       absorbing
               D       sinking                                                                          (1)

    1.9        ONE method of displaying information in digital systems is through the use
               of a ...

               A       keypad.
               B       light-emitting diode.
               C       light-dependent resistor.
               D       photo diode.                                                                     (1)

    1.10       An up/down counter is used as an application in …

               A       frequency dividers.
               B       mine-winding gears.
               C       CNC machines.
               D       lifts.                                                                           (1)

    1.11       Choose the correct JK input combinations that will produce a '1' (high) on the
               output of the JK flip-flop:

               A       J = 0 and K = 0
               B       J = 1 and K = 0
               C       J = 0 and K = 1
               D       J = 1 and K = 1                                                                  (1)

    1.12       Microcontrollers can be programmed in various ways. One of the methods to
               program a microcontroller is to use a flow chart. A flow chart is defined as a ...

              A       block diagram with instructions in the order of execution.
              B       block diagram of the operation of the microcontroller.
              C       block diagram of the construction of the microcontroller.
              D       range of data that shows the flow of data to the microcontroller.                 (1)   2024

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    1.13       With reference to microcontrollers, the term ROM means …

               A       read-only memory.
               B       read-output memory.
               C       read-onset memory.
               D       random-only memory.                                                           (1)

    1.14       A device that converts parallel data from the host processor into a serial data
               stream is known as a/an …

               A       universal asynchronous receiver transmitter (UART).
               B       central processing unit (CPU).
               C       serial peripheral interface (SPI).
               D       inter-integrated circuit (I2C).                                               (1)

    1.15       The process that allows a task to be repeated again and again is called ….

               A       debugging.
               B       data flow lines.
               C       looping.
               D       a flow diagram                                                                (1)
                                                                                                     [15]

    QUESTION 2: OCCUPATIONAL HEALTH AND SAFETY

    2.1        State TWO unsafe acts that would be regarded as dangerous practices by a
               user when operating machinery.                                                        (2)

    2.2        With reference to the Occupational Health and Safety Act, 1993 (Act 85 of
               1993), give TWO examples that are considered to be offences when reporting
               to the safety inspector.                                                              (2)

    2.3        Discuss the general duties that manufacturers perform when designing or
               manufacturing articles used at work.                                                  (2)

    2.4        Define a non-critical incident.                                                       (2)

    2.5        Describe a dangerous effect that a current of 200 mA has on the human body.           (2)
                                                                                                     [10]

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    QUESTION 3: SWITCHING CIRCUITS

    3.1        State ONE effect of switch bounce in electronic circuits.                                (1)

    3.2        FIGURE 3.2 below shows the basic circuit diagram of an op-amp bistable
               multivibrator with its input and output waveforms. Answer the questions that
               follow.

                                           C1                  +9 V
                           Trigger
                            input                                               Output

                                                                           R2
                                                 R1             -9 V

                                                                           R3

                                                  1       2       3    4

                                                                                Trigger
                                        0
                                                                                 input

                                 + VSAT

                                        0                                       Output

                                   -VSAT

                                    FIGURE 3.2: BISTABLE MULTIVIBRATOR

               3.2.1        Explain feedback with reference to the circuit.                             (2)

               3.2.2        Explain how the capacitor reacts when a positive trigger pulse is
                            applied to the input of the circuit.                                        (2)

               3.2.3        Describe the operation of the circuit when a negative trigger pulse
                            is applied to the input.                                                    (3)

               3.2.4        Explain why the output does not change when trigger pulse 2 is
                            applied.                                                                    (3)

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    3.3        Refer to FIGURE 3.3 below and answer the questions that follow.

                                                              +9V

                                             R2           R1
                                            47 kΩ        22 kΩ

                                                                                 8     4
                                                                            7                  Output
                                                                            6    555       3

                                                                            2                            R4
                                                                                 5     1
                                                                                                        470 Ω
                                             Trigger
                         1                                C1              C2
                 Input                                  220 µF         0,01 µF                 LED
                         0

                                     FIGURE 3.3: MULTIVIBRATOR CIRCUIT

               3.3.1         Identify the multivibrator circuit in FIGURE 3.3.                                       (1)

               3.3.2         State the function of resistor R2 in this circuit.                                      (2)

               3.3.3         Draw the output of the circuit for the given input on the ANSWER
                             SHEET for QUESTION 3.3.3.                                                               (3)

               3.3.4         Determine the voltage at which the circuit will reset to its resting
                             state. Give a reason for the answer.                                                    (2)

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    3.4        Refer to FIGURE 3.4 below and answer the questions that follow.

                                                                            +9 V
                                R2
                               1 kΩ
                                                     7     8       4                        T
                              R1                                           Output
                            100 kΩ                                     3
                                                          555
                                                     6
                                                     2 1       5
                                                                                       t1     t2
                               C1                                                    70 ms 69,3 ms
                              1 µF                                    C2
                                                                   0,01 µF

                                     FIGURE 3.4: ASTABLE MULTIVIBRATOR

               3.4.1        Explain why the output of the circuit changes state continually.                            (4)

               3.4.2        Explain why t1 and t2 are not equal.                                                        (2)

               3.4.3        Calculate the frequency of the output.                                                      (3)

    3.5        FIGURE 3.5 below shows an op-amp as comparator. Answer the questions
               that follow.

                                                                                    +9 V
                                                                    R1
                                                                   4,5 V                   +9 V
                     +9 V
                                                         VIN                        -
                                                                                                         VOUT
                                                                                    +
                       0
                                                 t               R2                        -9 V
                                                                2k2 Ω
                                                                                                         0V

                                     FIGURE 3.5: OP-AMP AS COMPARATOR

               3.5.1        Determine the value of the reference voltage.                                               (1)

               3.5.2        Determine the resistance of R1. Motivate your answer.                                       (2)

               3.5.3        Draw the output voltage for the given input on the ANSWER
                            SHEET for QUESTION 3.5.3.                                                                   (3)

               3.5.4        Explain how an increase in the value of R1 will affect the voltage
                            across R2.                                                                                  (2)

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    3.6        FIGURE 3.6 below shows the circuit diagram of an inverting summing
               amplifier.

                     0,1 V       V1         C1        R1 2k2 Ω                 RF 33 kΩ
                                      t

                                            C2        R2 2k2 Ω                   +10 V
                     0,2 V      V2
                                                                           -
                                      t
                                            C3        R3 2k2 Ω
                                                                           +
                     0,3 V      V3                                                             VOUT
                                                                                 -10 V
                                      t

                                          FIGURE 3.6: SUMMING AMPLIFIER

               3.6.1         Explain the purpose of a summing amplifier.                                        (3)

               3.6.2         Given:

                             R1 = R2 = R3        =     2,2 kΩ
                                       RF        =     33 kΩ
                                      VCC        =     +/- 10 V
                                        V1       =     0,1 V
                                        V2       =     0,2 V
                                        V3       =     0,3 V

                             Calculate the output voltage if RF is set to 33 kΩ.                                (3)

               3.6.3         State why the output falls to 0,6 V when RF is set to 2 200 Ω.                     (1)

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    3.7        Refer to FIGURE 3.7 below and answer the questions that follow.

                             +V                                 C
                                                      Input                   Output
                                0
                                                  t
                                                                          R

                                  FIGURE 3.7: PASSIVE RC DIFFERENTIATOR

               3.7.1        Draw the output of the circuit for the given input on the ANSWER
                            SHEET for QUESTION 3.7.1.                                                   (2)

               3.7.2        Explain the operation of the circuit during the first positive square
                            wave.                                                                       (3)

               3.7.3        Illustrate, by means of a basic circuit diagram, how the circuit
                            above can be changed to a passive integrator.                               (2)
                                                                                                        [50]

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    QUESTION 4: SEMICONDUCTOR DEVICES

    4.1        Determine the output state of the op amp in FIGURE 4.1 below for the
               conditions in TABLE 4.1 when V1 and V2 are in phase.

                                                                  +V
                             V1                          -
                                                                                   Vout

                             V2                           +
                                                                    -V

                                                                                   0V

                                    FIGURE 4.1: OPERATIONAL AMPLIFIER

                                  VIN                                       VOUT
               4.1.1        If V1 < V2           VOUT will be …

               4.1.2        If V1 = V2           VOUT will be …

                                                              TABLE 4.1                                    (2)

    4.2        Study FIGURE 4.2 below and answer the questions that follow.

                                                              RF = 10 kΩ

                                        RIN = 1 kΩ                       +15 V
                                                                _
                                                                                   VOUT
                               VIN = 60 mV                        +
                                                                         -15 V
                                                                                   0V

                            FIGURE 4.2: INVERTING OPERATIONAL AMPLIFIER

               4.2.1        Explain why op amps are not frequently used in open-loop mode.                 (2)

               4.2.2        Explain the term bandwidth as one of the characteristics of
                            operational amplifiers.                                                        (2)

               4.2.3        Calculate the output voltage.                                                  (3)

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    4.3        Refer to FIGURE 4.3 below and calculate the feedback resistance (RF) that is
               needed if the input resistance is 2 kΩ when the op amp is supplied with an
               input voltage of 0,5 V and produces an output voltage of 4 V.

                                                             +

                                                             _
                                                                         RF
                 VIN = 0,5 V
                                                                                  VOUT = 4 V

                                                                  RIN = 2 kΩ

                                    FIGURE 4.3: OPERATIONAL AMPLIFIER

               Given:

               VIN  = 0,5 V
               VOUT = 4 V
               RIN  = 2 kΩ                                                                           (3)

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    4.4        Refer to FIGURE 4.4 below and answer the questions that follow.

                                                                                                    +Vcc
                           0V        1                                                           8 Supply
                                             5 kΩ                     5 kΩ                5 kΩ

                         Trigger     2                                                           7

                                                          +   _                   +   _

                                                                      R   S
                          Output     3                                                           6   Threshold
                                                                      Flip
                                                                      flop

                                                 Output           Q           Q
                                                 driver

                          Reset                                                                      Control
                                     4                                                           5
                                                                                                     voltage

                                                      FIGURE 4.4: 555 IC

               4.4.1        Label pin 7.                                                                                      (1)

               4.4.2        Name ONE application of a 555 IC when used in monostable
                            mode.                                                                                             (1)

               4.4.3        Briefly describe the function of pin 4.                                                           (2)

               4.4.4        Name TWO modes of operation for the 555 IC.                                                       (2)

               4.4.5        Explain the function of the threshold input on a 555 IC.                                          (2)
                                                                                                                              [20]

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    QUESTION 5: DIGITAL AND SEQUENTIAL DEVICES

    5.1        Explain polarisation when used in the operation of a liquid crystal display
               (LCD.)                                                                                (3)

    5.2        Explain the difference between common anode and common cathode in a
               LED seven-segment display.                                                            (4)

    5.3        FIGURE 5.3 below represents an incomplete block diagram of a three-bit
               parallel adder. Complete and label the diagram of this adder on the ANSWER
               SHEET for QUESTION 5.3.

                                 B2 A2                B1 A1            Bo Ao

                                            Ci                  Ci

                                  Co                   Co              Co

                                 Ʃ3       Ʃ2

                                                      FIGURE 5.3                                     (7)

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    5.4    Refer to FIGURE 5.4 below and determine the binary code at the output when
           switch 7 is pressed. Write the answers on ANSWER SHEET 5.4.1.

                                                                                 +5V

                                                                                   &          A0

                                                                                   &         A1
                                                                                                 Outputs

                                                                                   &         A2

                                                                                   &         A3

                9      8       7    6      5       4     3     2     1

                                                                            0V

                                                        FIGURE 5.4                                           (4)

    5.5    Explain the term pulse triggering as used in flip-flops.                                          (2)

    5.6    Refer to FIGURE 5.6 below of a full adder and complete the logic circuit on
           ANSWER SHEET 5.6 using two half adders and an OR gate.

                                                                           ∑
                                          C in
                                                                         (sum)

                                               A             FA
                                                                         C out
                                               B

                                                 FIGURE 5.6: FULL ADDER                                      (6)

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    5.7        Refer to FIGURE 5.7 of a clocked JK-type flip-flop below and answer the
               questions that follow.

                                                               SET

                                                         J           Q

                                                         K     CLR
                                                                     Q
                                         FIGURE 5.7: JK-TYPE FLIP-FLOP

               5.7.1          Complete the       logic   circuit     of   this   flip-flop   on    ANSWER
                              SHEET 5.7.1.                                                                           (6)

               5.7.2          Complete the output waveforms of this flip-flop on ANSWER
                              SHEET 5.7.2. Assume that Q starts LOW.

                                         1          2            3           4           5            6
                         CLK

                          J

                          K

                          Q

                                                             FIGURE 5.7.2                                            (6)

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    5.8       FIGURE 5.8 below shows a three-stage ripple counter and answer the
              questions that follow.

                                   1                  A                              B                       C

                                                                           SET                     SET
                                         J       Q                     J         Q             J         Q
               Input clock
                 pulses
                                         K       Q                     K CLR Q                 K CLR Q
                                             FF0                           FF1                     FF2

                                 FIGURE 5.8 THREE-STAGE RIPPLE COUNTER

            5.8.1      Complete the timing diagrams for this counter on ANSWER SHEET
                       5.8.1.

                           Clock
                                                 1          2         3              4   5         6
                           pulses

                         Output A

                         Output B

                         Output C

                                                              FIGURE 5.8.1                                        (8)

               5.8.2         State whether the circuit in FIGURE 5.8 is synchronous or
                             asynchronous.                                                                       (1)

    5.9        State a disadvantage of the up/down counter.                                                      (1)

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    5.10 Refer to shift registers and complete the sketch of a four-bit serial-in: parallell-out
         shift register using flip-flops on the ANSWER SHEET for QUESTION 5.10 and
         show ALL the inputs and outputs.

                                             QA                 QB      QC                 QD

                  Clear

                                                       FIGURE 5.10                                 (7)
                                                                                                   [55]

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    QUESTION 6: MICROCONTROLLERS

    6.1        State TWO uses of a microcontroller as used in commercial devices.                              (2)

    6.2        Refer to the block diagram in FIGURE 6.2 below and answer the questions
               that follow.

                                                           CPU

                                                     ROM

                                                                       I/O

                                                     RAM

                                                      FIGURE 6.2

               6.2.1        Identify the block diagram in FIGURE 6.2 above.                                    (1)

               6.2.2        State the basic function that the random access memory (RAM)
                            performs.                                                                          (2)

               6.2.3        Write out the abbreviation CPU in full.                                            (1)

    6.3        Refer to FIGURE 6.3 below and answer the questions that follow.

                                          A                        B         Input and output

                                                       Control bus

                        C                             Address bus

                                                        Data bus

                                                      FIGURE 6.3
               6.3.1        Label A, B and C.                                                                  (3)

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               6.3.2        State the function of the following:

                            (a)    Control bus                                                        (2)

                            (b)    Data bus                                                           (3)

               6.3.3        Define the term interface.                                                (2)

    6.4        Refer to the block diagram in FIGURE 6.4 below of a CPU with registers and
               answer the questions that follow.

                                                   CPU
                 Input                                                 Clock           Output
                                                 Accumulator
                device                                                                 device

                                                          CIR          PC

                                                   MDR                 MAR

                                                         Memory unit

                                                          Secondary
                                                           Storage

                                                      FIGURE 6.4

               6.4.1        Explain how the data is processed once it enters the current
                            instruction register (CIR) from the MDR.                                  (3)

               6.4.2        Describe the function of the accumulator.                                 (2)

               6.4.3        State the TWO types of registers that are used within the CPU.            (2)

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    6.5        Refer to communication protocols and answer the questions that follow.

               6.5.1        Define communication protocols.                                           (2)

               6.5.2        Explain the differences between simplex communication and
                            half-duplex communication.                                                (4)

    6.6        Refer to serial communication interface and answer the questions that follow.

               6.6.1           Explain the mode of operation of the serial peripheral interface
                               (SPI).                                                                 (3)

               6.6.2           State TWO disadvantages of SPI.                                        (2)

    6.7        Refer to the RS-485 communication protocol and answer the following
               questions.

               6.7.1          State the maximum cable length.                                         (1)

               6.7.2          State the mode of operation.                                            (1)

               6.7.3          Name TWO devices that can be used with the RS-485 interface.            (2)

    6.8        Refer to software of microcontrollers and describe an instruction cycle.               (3)

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6.9        Refer to the incomplete flow chart below of a monostable device which has
           only one stable state. It changes state when it is triggered by an input, and
           stays in that state for 5 seconds and then returns to its original state.

           Draw a complete flow chart for this device on the ANSWER SHEET for
           QUESTION 6.9.

                                                         Start

                                                  FIGURE 6.9                                 (9)
                                                                                             [50]

                                                                               TOTAL:        200

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                                                 FORMULA SHEET
SEMICONDUCTOR DEVICES
          V          RF                           RF
Gain A V  OUT          OR          AV  1
           VIN       R IN                         RIN
               R 
VOUT  VIN    F 
               R IN 
                 R 
VOUT  VIN  1  F 
                 R IN 

FLOW CHART SYMBOLS IN PICAXE

                                Process

                                Decision

                                Terminator

                                   Data

SWITCHING CIRCUITS
           R        R         R 
VOUT    V1 F  V2 F  ...VN F 
           R1       R2        RN 
             VOUT         VOUT
Gain A V         
              VIN   V1  V2  ...VN 
VOUT   (V1  V2  ...VN )

      1
 F
      T

    Copyright reserved

### Page 24

Electrical Technology: Digital Electronics                           DBE/May/June 2024
                                                 SC/NSC Confidential

    CENTRE NUMBER:

    EXAMINATION NUMBER:

    ANSWER SHEET

    QUESTION 3: SWITCHING CIRCUITS

    3.3.3
                         1
                     Input

                         0

                         +V

                     Output                                            Transfer mark to
                                                                       answer book

                         0
                                                 t
                                                                                   MOD

                                                     FIGURE 3.3.3                            (3)

    3.5.3
                 +9 V

                 Vref

                     0

                 +9 V

                     0                                                 Transfer mark to
                                                                       answer book

                 -9 V
                                                                                   MOD

                                                     FIGURE 3.5.3                            (3)

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### Page 25

Electrical Technology: Digital Electronics                           DBE/May/June 2024
                                                 SC/NSC Confidential

    CENTRE NUMBER:

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    3.7.1

                         +V
                     Input

                              0
                                                 t
                      +V
                  Output

                             0                                         Transfer mark to
                                                                       answer book

                             -V
                                                                                   MOD

                                                     FIGURE 3.7.1                            (2)

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### Page 26

Electrical Technology: Digital Electronics                                 DBE/May/June 2024
                                                 SC/NSC Confidential

    CENTRE NUMBER:

    EXAMINATION NUMBER:

    ANSWER SHEET

    QUESTION 5: DIGITAL AND SEQUENTIAL DEVICES

    5.3
                                 B2 A2                 B1 A1           Bo Ao

                                            Ci                  Ci

                                  Co                    Co             Co

                                 Ʃ3        Ʃ2

                                                                               Transfer mark to
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                                                                                           MOD

                                                      FIGURE 5.3                                   (7)

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### Page 27

Electrical Technology: Digital Electronics                                    DBE/May/June 2024
                                                 SC/NSC Confidential

    CENTRE NUMBER:

    EXAMINATION NUMBER:

    ANSWER SHEET

    5.4

                                                                            +5V

                                                                              &          A0 =

                                                                              &          A1 =
                                                                                            Outputs

                                                                              &          A2 =

                                                                              &          A3 =

                     9     8      7    6     5     4    3     2    1

                                                                       0V

                                                                                  Transfer mark to
                                                                                  answer book

                                                                                              MOD

                                                       FIGURE 5.4                                     (4)

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### Page 28

Electrical Technology: Digital Electronics                            DBE/May/June 2024
                                                 SC/NSC Confidential

    CENTRE NUMBER:

    EXAMINATION NUMBER:

    ANSWER SHEET

    5.6
                                                                         ∑
                                C in
                                                                       (sum)

                                  A

                                                                       C out
                                  B

                                                                           Transfer mark to
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                                                                                       MOD

                                                      FIGURE 5.6                              (6)

     5.7.1

                      J
                                                                                       Q

                     CLK

                                                                                       Q
                     K

                                                                           Transfer mark to
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                                                                                     MOD

                                                     FIGURE 5.7.1                             (6)

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### Page 29

Electrical Technology: Digital Electronics                                 DBE/May/June 2024
                                                 SC/NSC Confidential

    CENTRE NUMBER:

    EXAMINATION NUMBER:

    ANSWER SHEET

   5.7.2

                                   1             2        3            4   5       6
                     CLK

                     J

                     K

                     Q

                                                                               Transfer mark to
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                                                                                         MOD
                                                     FIGURE 5.7.2                                  (6)

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### Page 30

Electrical Technology: Digital Electronics                                       DBE/May/June 2024
                                                      SC/NSC Confidential

    CENTRE NUMBER:

    EXAMINATION NUMBER:

    ANSWER SHEET

     5.8.1

                      Clock
                                         1              2         3         4    5        6
                      pulses

                     Output A

                     Output B

                     Output C

                                                                                     Transfer mark to
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                                                                                                 MOD
                                                          FIGURE 5.8.1                                   (8)
    5.10

                                                 QA                 QB          QC                 QD

                     Clear

                                                                                     Transfer mark to
                                                                                     answer book

                                                                                                 MOD

                                                            FIGURE 5.10                                  (7)

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### Page 31

Electrical Technology: Digital Electronics                            DBE/May/June 2024
                                                 SC/NSC Confidential

    CENTRE NUMBER:

    EXAMINATION NUMBER:

    ANSWER SHEET

    QUESTION 6: MICROCONTROLLERS

    6.9.2
                                                             Start

                                                                       Transfer mark to
                                                                       answer book

                                                                                   MOD
                                                      FIGURE 6.9                              (9)

Copyright reserved

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