FREQUENCY CANCELLOR DESIGN
SITI HASMAH BINTI JAMALI
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Universiti Malaysia Sarawak 2000
TK 7867 S623 2000
P. KHIDMAT MAKLUMAT UNI MAS
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SITI HASMAH BINTI JAMALI
Tesis Dikemukakan Kepada
Fakulti Kejuruteraan, Universiti Malaysia Sarawak Sebagai Memenuhi Sebahagian daripada Syarat
Penganugerahan Sarjana Muda Kejuruteraan
Dengan Kepujian (Kejuruteraan Eletronik dan Telekomunikasi) Mac 2000
Borang Penyerahan Tesis Universiti Malaysia Sarawak
R13a BORANG PENYERAHAN TESIS
Judul: Frequency Cancellor Design
Saya
SESI PENGAJIAN: 1997/2000 SITI HASMAH BINTI JAMALI
(HURUF BESAR)
mengaku membenarkan tesis im disimpan di Pusat Khidmat Maklumat, Universiti Malaysia Sarawak dengan syarat-syarat kegunaan seperti berikut:
1. Hakmilik kertas projek adalah di bawah nama penulis melainkan penulisan sebagai projek bersama dan di biayai oleh UNIMAS, hakmiliknya adalah kepunyaan UNIMAS.
2. Naskah salinan di dalam bentuk kertas atau mikro hanya boleh dibuat dengan kebenaran bertulis daripada penulis.
3. Pusat Khidmat Maklumat Akademik, UNIMAS dibenarkan membuat salinan untuk pengajian mereka.
4. Kertas projek hanya boleh diterbitkan dengan kebenaran penulis. Bayaran royalti adalah mengikut kadar yang dipersetujui kelak.
5. * Saya wewAetier4sn/tidak membenarkan Perpustakaan membuat salinan kertas projek ini sebagai bahan pertukaran di antara institusi pengajian tinggi.
6. ** Sila tandakan ( )
SULIT (Mengandungi maklumat yang berdarjah keselamatan atau kepentingan Malaysia seperti yang termaktub di dalam AKTA RAHSIA RASMI 1972).
TERHAD (Mengandungi maklumat TERHAD yang telah ditentukan oleh organisasi/badan di mana penyelidikan dijalankan).
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Disahkan oleh
(TANDATANGAN PENYELIA) Alamat Tetap: 156 Jalan Bunga Teratai
Kampun Pinang Jawa.
93050 Kuching Sarawak.
Al-Khalid Othman Nama Penyelia
Tarikh: 27 Mac 2000 Tarikh: 27 Mac 2000
CATATAN *
**
TIDAK TERHAD
Potong yang tidak berkenaan
Jika Kertas Projek ini SULIT atau TERHAD, sila lampirkan surat daripada pihak berkuasa/organisasi berkenaan dengan menyertakan sekali tempoh kertas projek.
This project report attached hereto, entitled " Frequency Cancellor Design". Prepare and submitted by Siti Hasmah Jamali as a partial fulfillment of the requirement for the degree of Bachelor of
Engineering with honours (Electronic and Telecommunication) is hereby read and approved by:
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Al Khalid Othman Date
Supervisor
ACKNOWLEDGEMENTS
One of the primary driving forces behind this completed project and design problems was the University of Malaysia Sarawak (UNIMAS), especially the Faculty of Engineering UNIMAS, Electronic and Telecommunication Program.
It is obvious that the progress and development of this project needs the support of many people. First of all I would to thank the lecturer behind this development of the project that is Mr. Al-Khalid Bin Othman as a supervisor and also for his support and all his advice that driven me in completing this project. It also goes to Mr. Wan Abu Bakar and Mr. Zakaria Bin Idris for their support in term of supplying all the equipment and components for this project.
Also not forget to my beloved family as they have been very patient for all the time I have not been with them, to all my special friends for their help and their guides to completed this project.
After all thanks a lot for the involvement of other people either their contribution to this project indirectly or directly. Last but not least thanks to I would like to thank all the lecturers for this three-year's guidance and also to everyone your cooperation is highly appreciated.
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ABSTRAK
Dalam litar elektronik kerap kali diperlukan pemisahan satu jalur frekuensi daripada jalur frekuensi yang lain. Tugas ini dilakukan oleh penuras
"filter" yang membenarkan satu jalur frekuensi melaluinya dan memotong jalur frekuensi yang lain daripada melaluinya. Penggunaan alat penuras adalah penting seperti contoh dalam telekomunikasi iaitu mengurangkan kesan herotan dan juga berperanan dalam menghalang frekuensi yang tidak diperlukan. Dalam projek ini ia diaplikasikan pada penggunaan penerus gelombang penuh "full wave rectifier". Penerus ialah proses penukaran arus ulang-alik menjadi arus terus iaitu dengan menggunakan peranti"diode" yang membenarkan arus mengalir pada satu arah sahaja. Penerus digunakan dalam unit bekalan kuasa arus terus dan untuk beberapa tugas lain seperti penyahmodulat.
Penerusan gelombang penuh akan mengeluarkan kedua-dua separuh isyarat tetapi kedua-duanya sama arah. Masukan arus ulang-alik biasanya diambil dari bekalan kuasa utama yang akan melalui pengubah"transformer".
Pada kebanyakan bekalan kuasa arus terus, pengubah digunakan sebelum penerus bagi menukarkan masukan arus ulang-alik ke aras voltan yang dikehendaki. Nisbah belitan pengubah menentukan aras arus terus yang dapat dikeluarkan oleh bekalan kuasa itu. Heluaran penerus mempunyai aras arus
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terus bersama perubahan arus ulang alik yang besar. Bentuk gelombang yang dikenali sebagai voltan arus terus denyut yang ma ih belum boleh digunakan sebagai bekalan arus terus yang memuaskan. Bagi mengeluarkan kandungan arus ulang-alik litar pelicin digunakan yang merupakan penapis laluan rendah yang membenarkan arus terus melaluinya dan mengurangkan riak "ripple".
Frekuensi riak ini ditentukan oleh jenis penerus yang digunakan iaitu penerus separuh gelombang penuh akan mengeluarkan frekuensi riak yang sama manakala penerus gelombang penuh akan memberikan frekuensi riak dua kali ganda frekuensi masukan.
Walaupun riak ini dapat dikurangkan oleh litar pelicin iaitu terdiri daripada kapasitor dan perintang tetapi pada satu takat ia tidak dapat dikurangkan bagi memperolehi arus terus yang licin. Oleh itu penggunaan penerus notch "notch filter" digunakan bagi mengurangkan riak dan juga hanya membenarkan satu julat frekuensi sahaja melaluinya.
Tesis ini membincangkan tentang prinsip bagi kedua-dua litar, ciri yang harus dititikberatkan dalam menghasilkan litar tersebut dan juga keluaran yang harus diperolehi apabila mengaplikasikannya.
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ABSTRACT
In electronic circuit, the separation between one frequency and another frequency is needed. It is done by filter and it is applied where low-level signal must be amplified, there may be present one or more of an assortment of unwanted noise signal and for example ripple from full wave rectifier. The notch filter only allowed the desired signals would exit from the filter.
The best known application of full-wave rectifying techniques is in DC power supply circuits, which provide DC power outputs from AC line input and consists of little more than a transformer that converts the AC value, and a rectifier-filter combination that convert this new AC voltage into smooth DC of the desired voltage value.
Full wave rectifier will permits two input but in the same direction. AC obviously had taken from main power supply and thorough the transformer.
The input voltage to the rectifier is provided by secondary winding of
transformer. The transformer reduces the AC voltage obtained and appearing across the transformer's secondary terminals has a peak magnitude on the order of the DC voltage level desired from the power supply. The transformer also provides DC isolation between the AC power line and the DC can pass across the coupled windings of transformer.
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The output from rectifier produced the DC and the pulsating DC voltage is not pure DC, so capacitor and resistor is placed across the DC output
terminals of the bridge rectifier. It is used to reduce the ripple that has been produced by full wave rectifier. The ripple is depend on the types rectifier that is for half wave rectifier it produce the ripple same as for input frequency and for full wave rectifier it give double ripple frequency from the input frequency.
Eventhough the ripple can be removed by placing the capacitor and resistor but at the certain limit it can't give the smooth DC. The application of notch filter takes place by producing the smooth DC and allowed a certain frequency passed.
In this thesis it is include the principle for circuit, the design procedure and the expected output as it applied.
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Pusat Khidmat Maklumat Akademik UNIVERSITI MALAYSIA SARAWAK
TABLE OF CONTENT
APPROVAL LETTER APPROVAL SHEET THESIS TITLE
ACKNOWLEDGEMENT ABSTRAK
ABSTRACT
TABLE OF CONTENT LIST OF TABLES LIST OF FIGURES LIST OF APPENDICES
CHAPTER
PROJECT OVERVIEW 1.0 Introduction
1.1 Objective of the project 1.3 Project Outline
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1 2 3
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2 LITERATURE REVIEW 2.0 Filter circuit concepts
2.1 Advantages of active over passive circuits 2.2 Filter responses
2.2.1 Low pass filter 2.2.2 High pass filter 2.2.3 Band pass filter 2.2.4 Notch filter 2.3 Basic filter Theory
2.3.1 Filter Types
2.3.2 Butterworth Approximation 2.3.3 Chebyshev Approximation 2.3.4 Conclusion
2.4 Operational Amplifier (Op - amp) 2.4.1 The Inverting Circuits
2.4.2 The Non- Inverting Circuits 2.4.3 Conclusion
2.5 Low pass filter
2.5.1 The Two pole Low-pass filter 2.5.2 The Three Pole Low pass filter 2.6 High pass filter
2.6.1 Filter gain requirements
5 6 7 7 7 8 9 9 10 11 11 12 13 13 14 15 16 18 20 20 21
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2.7 Band-pass filter 2.7.1 Quality factor
2.7.2 Multiple feedback band pass filters 2.7.3 Circuit Analysis Frequency
2.7.1 Filter gain 2.8 The Notch Filter 2.8.1 Conclusion 2.9 Full wave rectifier
2.9.1 Comparison between two rectifier 2.9.2 Transformer
2.9.3 Transformer current ratings
3 HARDWARE DESIGN
3.0 Introduction
3.1 Design procedure for full wave rectifier 3.1.1. (A) DC design
3.1.1. (B) Procedure of choosing diodes 3.1.2. AC design procedure
3.2 Design procedure for notch filter 3.3 Schematic Design
3.3.1 Components
3.4 Printed Circuit Board(PCB) Design 3.4.1 PBC Preparation
3.4.2 Etching 3.5 Soldering
22 24 26 28 32 33 38 39 40 41 41
43 43 43 44 44
46 48 48 48 49 50
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4 RESULT AND DISCUSSIONS
4.0 Introduction 51
4.1 Test Equipment 51
4.2 Testing On Breadboards 52
4.2.1. Testing On full wave rectifier 52
4.2.2. Testing on notch filter 59
4.3 Theoretical Calculation 64
4.3.1 Theoretical Calculation for full wave rectifier 64 4.3.2 Theoretical calculation for notch filter 65
b CONCLUSION AND FURTHER WORKS
5.1 Conclusion 5.2 Further works
68 69
APPENDICES 71
REFERENCES 77
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LIST OF TABLES
TABLE PAGE
1.0 BUTTERWORTH 22
3.3.1 COMPONENTS USED IN PROJECT 48
4.0 TEST EQUIPMENT USED IN THE PROJECT 51
4.1 RESULT FOR NOTCH FILTER 66
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LIST OF FIGURES
FIGURE PAGE
1.0 COMPARISON OF FREQUENCY RANGE OF FILTER 6
2.2.1 LOW PASS FILTER CHARACTERISIC 7
2.2.2 HIGH PASS FILTER CHARACTERISTIC 8
2.2.3 BAND-PASS FILTER CHARACTERISTIC 8
2.2.4 NOTCH FILTER CHARACTERISTIC 9
2.3.1 CHARACTERISTIC OF FILTER RESPONSE 11
2.3.3 BUTTERWORTH AND CHEBYSHEV RESPONSE 12
2.4.1 INVERTING AMPLIFIER 13
2.4.2 NON-INVERTING AMPLIFIER CIRCUIT 14
2.5 SINGLE POLE LOW-PASS ACTIVE FILTER 16
2.5 A FREQUENXY RESPONSE 17
2.5.1A CIRCUIT FOR ACL< 1.586 18
2.5.1B CIRCUIT FOR A, L< 1.586 19
2.5.1C TWO POLELOW PASS FILTER FREQUENCY RESPONSE 19
2.5 HIGH PASS FILTER 21
2.7A BAND-PASS FILTER 23
2.7B BAND-PASS FILTER CHARACTERISTIC 23
2.7.2a 26
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2.7.2b 27
2.7.2c 27
2.8A, B SUMMING AMPLIFIER AND NOTCH FILTER CHARACTERISTIC 33 2.8.1A NOTCH FILTER
2.8.1B THE SIMPLIFIED NOTCH FILTER
2.9 FULL WAVE RECTIFIERS WITH TRANSFORMER 3.1a DESIGN OF FULL WAVE RECYIFIER
3.2 DESIGN FOR NOTCH FILTER
4.2.1 SHOWS THE NODE THAT BEEN TESTED 4.2. la OUTPUT FROM TRANSFORMER
4.2.1b CURRENT FLOW WHEN Vin IS POSITIVE 4.2. lc OUTPUT FOR Vin POSITIVE
4.2. ld FOR Vin NEGATIVE
4.2.1e OUTPUT FOR DIODE Dl AND D3 4.2.1f RESULT FOR NODE 2 & 3
4.2.1. gOUTPUT OF CAPACITOR
4.2.1. hOUTPUT WITH CAPACITOR lUf 4.2.1. i OUTPUT WITH 10uF
4.2.2 SHOW THE NODE THAT HAS BEEN TESTED 4.2.2a INPUT FOR NOTCH FILTER
4.2.2b OUTPUT FROM SUMMATION AND INTEGRATOR 4.2.2c OUTPUT OF BANDPASS FILTER
35 38 39 46 47 52 53 54 54
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56 56 57 58 59
60
61 62 63
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4.2.2d OUTPUT FROM NOTCH FILTER 4.3.1 GRAPH FOR FULL WAVE RECTIFIER 4.3.2 GRAPH FOR NOTCH FILTER
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LIST OF APPENDICES
APPENDICE
A SCHEMATIC DESIGN
B SCHEMATIC DESIGN HAS TO BE REDRAWN C LAYOUT OF PCB
D BUILT ON BREADBOARD
E OUTPUT FROM OSCILLOSCOPE F OUTPUT SAVING BY LECROY
PAGE 71 72 73 74 75 76
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CHAPTER 1
PROJECT OVERVIEW
1.0 INTRODUCTION
"Frequency Cancellor Design" is used to remove the unwanted noise signal and allowed the desired signals would exit from the filter and it is the combination of full wave rectifier and notch filter. Why notch filter is needed? It is because in application where low-level signal must be
amplified, there may be present one or more of an assortment of unwanted noise signal and for example ripple from full wave rectifier. The notch filter only allowed the desired signals would exit from the filter.
The notch filter is particularly useful for rejecting unwanted line frequencies such as 50, 60, 100, 120 or 400 Hz within sharply defined limits.
Applications are in such diversified areas as communications, telemetry, control, analog computers or sensitive chemical measurements. The operational - amplifier make use in application of overload protection on the input and output, no latch-up when the common mode range is
exceeded. The op-amp was applied to the solution of such mathematical functions as integrated, differentiation and summing by electronic means.
The tuned circuits are used primarily in communication electronics.
Audio and video circuits make extensive use of tuned circuits. Notch filter
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can be used to eliminate the low frequency noise that can be generated in many audio systems. The application is to split the audio signal from a stereo, television or other communications system so that the high frequency of the audio goes to a small high frequency and the low
frequency goes to relatively large low frequency speaker. It can be used to eliminate the 30 Hz that can be produced by turntable. By tuning the notch filter to 30Hz, this noise will be blocked by the filter while the high audio frequencies are allowed to pass.
The best known application of full-wave rectifying techniques is in DC power supply circuits, which provide DC power outputs from AC line input and consists of little more than a transformer that converts the AC value, and a rectifier-filter combination that convert this new AC voltage into smooth DC of the desired voltage value.
Filters can be classified as passive and active filter, the main
disadvantage of passive filter is there are lack power supply is required. On the other hand the active filter can use operational amplifier in order to isolate each section of the filter from the source and load impedance effects.
1.1 OBJECTIVE OF THE PROJECT
Frequency Cancellor Design is used to removed the unwanted frequency. Normally by using the capacitor in order to reduce the ripple from full wave rectifier is still not satisfied and the other alternative is by using the notch filter.
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The objective of this project is to design and implement the
frequency cancellor design, which employed the notch filter by using the operational amplifier and full wave rectifier. It is used to reduce the ripple that has been produced by full wave rectifier. Beside of using the capacitor as a filter to get a smooth DC in full wave rectifier but it is still not smooth as well as using the notch filter. By using the capacitor it is achieved by using the higher value of capacitor for example 1OuF, 500uF and more and at a certain value the ripple can't get rid off and the smooth DC cannot be achieved. Its can be done by using the notch filter as an output of full wave rectifier in order to get a smooth DC as possible and rejected the unwanted frequency. The project also makes use of Protel's software for schematic and PCB design.
1.2 PROJECT OUTLINE
Chapter 1 consists of the introduction and the objective of the project. It describes briefly about frequency cancellor design, which made up of full wave rectifier and notch filter and also it's application especially in the communication system.
Chapter 2 discussed about the theory of full wave rectifier and the active filter, the example of calculation also included. Chapter 3 consists of hardware design procedure and Chapter 4 includes the result and
discussions by calculation and hardware testing for both full wave rectifier and notch filter.
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And lastly as a conclusion in Chapter 5 discussed whether or not the objective of the project is achieved and the experienced as project goes on.
It also include the further works that can be done regarding to the application of the project.
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CHAPTER 2
LITERATURE REVIEW
2.0 FILTER CIRCUIT CONCEPT
A filter is an electrical network, which is designed to modify an electrical signal applied to its input terminals. Other filters may be designed to pass a range of frequencies about a given selected frequency, rejecting frequencies outside the selected band and vice versa. The
fundamental principles of electrical wave filters were outlined by Wagner in Germany and Campbell in the USA around the year 1915. There are many ideas and techniques related to the modern network theory and feedback analysis, for examples the Bode and Black on the stability of amplifiers. The choice of type of filter from the large range of filters must be influenced by several factors, some of which are: complexity, ease of tuning and whether or not power supplies may be required. [1]
Filters may be classified as a passive or active. By referring to figure 1.0 it can be seen that active filter realization are more advantageous at lower frequencies than in the case for passive types, although the reverses true at higher frequencies.
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Active R-C
L-C Passive
Distributed wave guide
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º F1 102 103 104 106 106 10' 108 109 1010 1011 (Hz) FIGURE 1.0 COMPARISON OF FREQUENCY RANGE OF FILTER [1]
2.1 ADVANTAGES OVER PASSIVE FILTER
Passive filters are the combinations of resistance and capacitance or inductance and capacitance and can be designed to cover a wide band of frequencies (typically 10 Hz to 500 Hz). The advantages over active
circuits in that they do not required an external power supply and that they have low sensitivities to component variation. At lower frequencies the large coils having low Q factors. The coils usually require efficient magnetic cores and special winding technique to enable a reasonable level of quality, which increased the cost. [11
Actives filter is the combination of resistors, capacitors and an active source, which is usually an operational amplifier. The main advantages over the passive types are that expansive and bulky coils are eliminated, circuit gain may be realized, and high input and low output impedance
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