soalan fault finding_pkm_2011.pdf

7/29/2019 Soalan Fault Finding_PKM_2011.pdf

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2011

PERTANDINGAN KEMAHIRAN MALAYSIA

(ELEKTRONIK)

SOALAN

PERINGKAT AKHIR

NAMA: ______________________________________

NO. KP: ______________________________________

JABATAN PEMBANGUNAN KEMAHIRANKEMENTERIAN SUMBER MANUSIA


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Project: Fault Finding And Repair

Time Limit: 2 hours

1.0 REQUIREMENTS

1.1 You have to find and repair 4 faults in the given circuit. A basic WaveformGenerator.

1.2 In order to carry out the required tasks, you may need to refer to the followingdocumentations:

Circuit Schematic Diagram

PCB Layout Diagram

Component List

1.3 Unless otherwise stated, all waveforms and voltages are measured with referenceto ground (0V).

.

2.0 BACKGROUND INFORMATION

The board consists of several basic circuits which connected together producesPWM waveforms. The test pins TP11 and TP12 show the PWM outputs. P3 headeroutput provides the product of the two waveforms.


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3.0 CIRCUIT DESCRIPTION

3.1 The overall circuit diagram in shown Figure 1.

3.2 The DC Power supply can be varied up to 60V by adjusting the VR1.

3.3 The waveform generated by the sine wave generator is inverted by the IC U7A andappears at the output OUT1/1 (TP8). The frequency of the waveform can beadjusted by changing the variable resistor, VR4. The variable resistor, VR5, is used tovary its amplitude and VR6 for adjusting the offset level.

3.4 The frequency and the amplitude of the square wave output at TP2 can be variedby adjusting VR3 and VR4 respectively.

3.5 The frequency and the amplitude of the triangle waveform can be varied byadjusting VR7 and VR9 respectively.

4.0 TEST EQUIPMENT REQUIRMENTS

Dual DC Power Supply 1 set

Digital Oscilloscope 1 set

Desktop link to Oscilloscope 1 set

Assortment of connecting cables 1 set

INSTRUCTIONS TO THE COMPETITOR

Please carry out this project as per the following steps:

(1) Competitors must carry out the fault finding and repair work. Also, on the faultfinding and repair answer sheet you must record the location of the fault, thedetail of the fault and the fault symbol. Use the Fault Symbol Table as areference for fault symbol.

(2) After finding the fault, if you need a component in order to repair it, you will bepermitted to order the new component from the expert. You are only allowed torequest for components on the component list.

(3) Make sure that you request the least supply of necessary components for this

project. Make note that a wrong request will lead to a reduction of 0,75 marks inyour overall score of this project.

(4) Repair the located faults. And, check that it operates correctly after repairing.


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THE SYMBOLS LIST OF THE FAILED STATE

Fault symbol Description Remark

Open(Part or wire)

Incorrect wiring(Part to part wire)

Short(Part or wire)

Incorrect polarity part(Including incorrect pin location due to misplacing)

Part with a large value(Resistor, Capacitor, Frequency, etc)

Part with a small value(Resistor, Capacitor, Frequency, etc)

?Incorrect part number or incorrect wiring connection

Defected

(Including partly broken)

Examples for filling in the answer table

If the value of R1 was too large or small,

Defective part Failed state symbol

Fault 1 R1or

If the polarity of diode D1 was opposite,


Fault 1 D1

If the line between Pin-1 of IC1 and Pin-2 of IC2 was open,


Fault 1 IC1(pin-1) IC2(pin-2)

If the line between Pin-1 of IC1 and Pin-2 of IC2 was incorrect wiring,


Fault 1 IC1(pin-1) IC2(pin-2)

If IC1 dose not operate(Broken),Defective part Failed state symbol

Fault 1 IC1


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THE ANSWER TABLE OF THE REPAIR STATE


Fault 1

Fault 2

Fault 3

Fault 4


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PARTS LIST

Item Parts name Parts value(Model) Qty Reference number

1 Timer NE555 1 U8

2 7-segment decoder 74LS47 2 U3 ,U5

3 4-bit comparator 74LS85 2 U6, U7

4 BCD counter 74LS90 2 U10, U11

5 One short M/V 74LS123 1 U2

6 BCD Up/Down counter 74LS192 2 U1, U4

7 Phase Locked Loop MC14046 1 U9

8 7-Segment FND-507(A-com) 2 LED1, LED2

9 Diode 1N4148 1 D1

10 Diode Zener 3V 1 D3

11 Light Emitting Diode EL204RD, 1 D2

12 Diode D_BRIGDE 1A 1 DB1

13 Capacitor for Ceramic 10nF 1 C18

14 Capacitor for Ceramic 100pF 1 C3

15 Capacitor for Ceramic 100nF 16C1, C2, C4, C6, C7, C8, C9,C10, C12, C13, C14, C16, C17,C19, C21

16 Capacitor for Electric 1000uF 1 C23



19 Capacitor for Electric 0.47uF 1 C26


21 Capacitor for Electric 4.7uF 1 C24

22 Capacitor for Ceramic 1000pF 3 C5,C11,C15

23 Resistor 39K, 0.25W, 1% 1 R21


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24 Resistor 10K, 0.25W, 1% 8R1, R2, R3, R11, R12, R13,R30, R31

25 Resistor 330, 0.25W, 1% 17R4, R5, R6, R7, R8, R9, R10,R14, R15, R16, R17, R18, R19,R20, R27,R33,R35

26 Resistor 6.8K, 0.25W, 1% 1 R22

27 Resistor 1M, 0.25W, 1% 1 R23

28 Resistor 100K, 0.25W, 1% 1 R24

29 Resistor 15K, 0.25W, 1% 1 R25

30 Resistor 470, 0.25W, 1% 2 R28,R29

31 Resistor 1K, 0.25W, 1% 1 R32

32 Resistor 4.7K, 0.25W, 1% 1 R34

33 Resistor 0.47, 1W, 1% 1 R26

34 Variable Resistor 100K, 1 VR2



37 Test Point Pin LC-2-G 4 TP1, TP2, TP3, TP4

38 Push button switch Tact PB 4-P 2 SW1, SW2

39 DIP Soket RIC-DIP-8 1 U8

40 DIP Soket RIC-DIP-14 2 U10, U11

41 DIP Soket RIC-DIP-16 7 U1, U2, U3, U4, U5, U6, U7,

42 Connector Header 2 1 J1

43 Transistor H1061 1 Q1

44 Transistor C1815 3 Q2, Q3,Q4


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COMPONENT LIST WHICH COMPETITORS ORDER FOR REPAIRING

Item Parts name Parts valueQty

ExpertsSignature

CompetitorsSignature

1

2

3

4

5

6

7

8

9

10

11

12

13

14

15

16


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SCHEMATIC DIAGRAM: FIGURE 1


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Schematic: DC Power Supply

SWC1

SWE2

TCAP3

GND4

-VIN5

VCC6

IPK7

DRVC8

U1

MC34063U

SWC1

SWE2

TCAP3

GND4

-VIN5

VCC6

IPK7

DRVC8

U2

MC34063U

12

P1

Header 2

VR25K

R6

1K

R71K

R3

1K

L1

220mH

L2120mH

C1

100uF/25V

222

C2

C4472

D1

D2UF4002

GND

GND GND GND

GND

+12V

GND

GNDGND

Q2TIP122

Q1TIP122

R1

0R1/1W

R2

0R1/1W

R5

0R1/1W

DC +12V INPUT


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GND

VCC

TP13

+12V

C19104

C18104

C17

100uF/25V

C20100uF/25V

IN

1

2

OUT

3

GND

U3 LM7805CT


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Schematic: Sine Wave Output

VR450K

VR3

5K

VR5100K

R8

4K7

R10 51K

R11 0R1

R9

4K7

R1215K

R13240K

R1410K

C10

474

C9

104

+12V

SIN ADJ1

SIN OUT2

TRI. OUT3(DUTY

4

ADJ)5

V+6

FM BIAS7

FM SWEEP8

SQU. OUT9

TIMING10

V-11

SIN ADJ 12

NC13

NC14

U4

XR8038

+12V

+12V

+12V

+12V

-VCC

-VCC

-VCC

-VCC

-VCC

+12V

-VCC

TP2

TP3

O

GND

R15

10K

R17

10K

R164K7

8

1

4

3

2

U5A

TL082ACJG

8

4

75

6U5BTL082AC

GND

-VCC

+12V

VR6100K

+12V

-VCC

S

SQUAREWAVE

R10

R11


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Schematic: Triangle output

2

3

11

4

11

U6A

TL084CN

5

6

72

4

11

U6B

TL084CNGND

+12V

-VCC

+12V

-VCC

GNDC11

104

C12

104

R18

100K

VR7

100K

VR9

100K

VR8

100K

-VCCTP5

TP6

+12V

-VCC

R20

10K

R19

10K

G

+12V

SQUAREWAVE

TRIANGLEWAVE


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Schematic: PWM Output

2

31

1

4

11

U8ALM324AN

5

67

2

4

11

U8BLM324AN

+12V

-VCC

-VCC

+12V

C14104

Q49013

Q39013

R28470R

R27470R

R26

10K

R25

10K

OUT1

OUT1/1

OUT2

VCC

VCC

GND

GND

+12V

-VCC

TP9

TP10

GND

GND

+12V

CMP1

CMP2

CMP1

CMP2

R29330R

R30330R

VCC

VCC

C15104

C116104

+12V

GND GND

+12V

,.,

'

;

.

.,

,,

,.

+12VU9 TLP250

U9 TLP250


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PCB COMPONENT LAYOUT


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PCB LAYOUT


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Pertandingan Kemahiran Malaysia (PKM)

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PARTS LIST

Item Parts name Parts value(Model) Qty Reference number

1 DC-to-DC ConverterControl Circuit MC34063U 2 U1,U2

2

Three-TerminalMedium CurrentPositive VoltageRegulator

MC78M05BT 1 U3

3Precision WaveformGenerator

XR8038 1 U4

4JFET-InputOperational Amplifier

TL082ACJG 2 U5,U7

5JFET-InputOperational Amplifier

TL084CN 1 U6

6

Transistor Inverter For AirConditionor IGBT Gate

Drive Power Mos Fet GateDrive

TLP250 2 U9,U10

7Quad Low-PowerOperational Amplifier

LM324AN 1 U8

8 Diode UF4007 1 D1

9 Diode UF4002 1 D2

10 Capacitor for Ceramic 222 1 C2



13 Capacitor for Ceramic 104 10C9, C11, C12,C13,C14,C15,

C16,C18, C19

14 Capacitor for Electric 100uF/25V 1 C1



17 Capacitor for Ceramic 100uF/25V 1 C17.C20

18 Resistor 0R1/1W 1 R1,R2,R5

19 Resistor 1K, 0.25W, 1% 4 R3, R4, R6, R7

20 Resistor 4K7, 0.25W, 1% 4 R8, R9,R16.R21

21 Resistor 51K, 0.25W, 1% 1 R11

22 Resistor 0R1, 0.25W,0.5% 1 R10


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23 Resistor 15K, 0.25W, 1% 1 R12

24 Resistor 240K, 0.25W, 1% 1 R13

25 Resistor10K

, 0.25W, 1%10

R14,R15,R17,R19,R20,R22,R23,R24,R25,R26

26 Resistor 100K, 0.25W, 1% 1 R18

27 Resistor 330, 0.25W, 1% 2 R29,R30

28 Resistor 470, 0.25W, 1% 2 R27,R28

29 Potentiometer 50K 1 VR1


31 Potentiometer 5K

1 VR3


33 Potentiometer 100K 5 VR5,VR6, VR7, VR8 ,VR9

34 Test Point Pin LC-2-G 16

TP1, TP2, TP3, TP4,TP5, TP6, TP7, TP8,TP9, TP10, TP11,TP12, TP13, TP14,

35 Inductor 220mH 1 L1

36 Inductor 120mH 1 L2

37 DIP Socket RIC-DIP-8 6 U1, U2,U5,U7,U9,10

38 DIP Socket RIC-DIP-14 3 U4,U6,U8

39 Connector Header 2 PIN 2 P1, P3

40 Connector Header 3 PIN 1 P2

41 Transistor TIP122 1 Q1,Q2

42 Transistor 9013 2 Q3,Q4


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EQUIPMENT, MACHINERY, INSTALLATIONS AND MATERIALS REQUIRED

Host country prepares the following equipments, machinery, installations and materials for each competitor

Item Qty Material Description Notes

1 1 Worktable with ESD protection W=1800 , D=900, H=750 [mm]

2 1 Office chair

3 1 Workstation Lamp

4 1 Oscilloscope 2CH, BW=100[MHz], 1GS/s

5 1 Universal Digital Multi-meter V, , A, etc

Proposal the Hot country prepares the following equipments, machinery, installations and materials.


1 10set All parts


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The competitor needs to prepare the following equipments, machinery, installations and materials.


1 Soldering Iron

2 Soldering Iron Stand

3 Solder wick or Solder Remover

4 Lead Bender

5 Pincer

6 Nipper

7 Wire Stripper

8 Scissors

9 Tweezers

10 IC pick

11 PCB stand

12 Parts box

13 Precise screwdriver For trimmer resistor

14 Screw driver + type

15 Screw driver - type

16 Scale 300mm

17 Template Electric Symbol

18 Safety Glasses

19 Cotton Glove

20 Brush

21 Industrial wiper

soalan fault finding_pkm_2011.pdf

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