midterm report research topic l pi t section impedance matching

Increasing Zcenter beyond min {Rload,Rs} reduces the Q of match and at the same time compromises the maximum power that can be transferred at the design frequency .... • In audio amplifi

HANOI UNIVERSITY OF SCIENCE AND TECHONOLOGY SCHOOL OF ELECTRICAL AND ELECTRONICS ENGINEERING

Midterm Report Analog Circuit 2

Research topic: L, Pi, T section impedance matching

Student: Dương Đức Mạnh Student’s ID: 20193229

Instructor: Dr Nguyen Nam Phong

Hanoi, 03/2023

Contents

1 Introduction 4

1.1 Impedance Matching 4

1.2 Matching Network (impedance transformer) 4

1.3 Research Requirements 4

2 Overview, Design and Calculation, Simulation of Matching Networks (L, Pi, T) 5

2.1 L matching network 5

Overview 5

Design and Calculation 7

Simulation 8

2.2 Pi matching network 10

Overview 10

Simulation 12

2.3 T matching network 14

Overview 14

Design and Calculation 14

Simulation 16

Reference 17

Figure 2 L matching simulation (for the exercise) 9

Figure 3 Pi matching networks: (a) view of a Pi network; and (b) as two back- -back L networks with a to virtual resistance, RV, between the networks 10

Figure 4 Pi network (back- -back L-networks) provides higher Qto 10

Figure 5 Value Table (Pi network) 12

Figure 6 ADS Schematic for 40 Ohm Center Impedance Design 12

Figure 7 Simulated Frequency Response of pi-networks for varying center Impedance 13

Figure 8 Increasing Zcenter beyond min {Rload,Rs} reduces the Q of match and at the same time compromises the maximum power that can be transferred at the design frequency 13

Figure 9 T network design approach 14

Figure 10 Value Table (T network) 15

Figure 11 ADS schematic for T matching network 16

Figure 12 T network simulation 16

1 Introduction

1.1 Impedance Matching

• Impedance matching is important in electrical engineering because it allows for maximum power transfer between two points In telephone systems, for example, minimizing echo on long-distance lines is achieved using match impedances The telephone hybrid coil, where two wires are converted into four wires can also be achieved via matching

• In audio amplifiers, impedances are not matched as it is typical for amplifiers to have output impedances that are lower than the load impedance for better speaker damping But for higher-power amplifiers, such as those that use vacuum tubes, impedance-changing circuits are used to get a low output impedance in order to better match the amplifier's performance to the load impedance

1.2 Matching Network (impedance transformer)

• A matching network, also called an impedance transformer, is used to create matched impedance between a source and a load (for example, between a power amplifier and

an antenna)

• Lossless matching networks consist of reactive components only; resistive components are avoided because they would dissipate power, whereas the matching network is intended to facilitate the transfer of power from source to load

• A straightforward, narrowband matching-network topology is the L network It consists

of two reactive components

• Calculator tools can be used to quickly design a matching network based on the source impedance, load impedance, and signal frequency

1.3 Research Requirements

Networks for Impedance Matching: T , Pi , T network

• Circuit Configuration

• Frequency Response

• Calculation of matching circuit

• Simulation for result of matching circuit

2 Overview, Design and Calculation, Simulation

of Matching Networks (L, Pi, T)

2.1 L matching network

Overview

The L-match impedance matching circuit is one of the circuits used to match the impedance between two points, usually a source and a load The circuit got its name because the inductor and the capacitor form an L-shape Note that the inductor and capacitor can be interchanged depending on the input If you need to block direct current, then the capacitor is placed near the source Otherwise, the inductor is placed near the source

The load impedance can be transformed up or down using matching network Simplest matching network is L-match The value of Q is determined by the ratio of R_{in} to R_{L}, and bandwidth is not controllable

Upward transform : R_{in}>R_L

Downward transform : R_{in}<R_L

There are 4 types of L network

Design and Calculation

Simulation

Figure 1 ADS Schematic for Linear AC Analysis of Circuit

Figure 2 L matching simulation (for the exercise)

Comment:

The match is perfect at the design frequency but, away from that frequency, we must accept the resulting frequency response

2.2 Pi matching network

Overview

networks with a virtual resistance, RV, between the networks

Design and Calculation

10

20

30

40

Figure 5 Value Table (Pi network)

Simulation

Figure 6 ADS Schematic for 40 Ohm Center Impedance Design

Figure 7 Simulated Frequency Response of pi-networks for varying center Impedance

Figure 8 Increasing Zcenter beyond min {Rload,Rs} reduces the Q of match and at the same time compromises the maximum power that can be transferred at the design frequency

2.3 T matching network

Overview

Figure 9 T network design approach

Design and Calculation

Zcenter L1 L2 C

2000

3000

5000

10000

Simulation

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Our course’s slides and books

L network and L network calculator:

https://analog.intgckts.com/impedance-matching/l-matching/

https://www.electronicdesign.com/technologies/communications/article/21800910/back- -to basics-impedance-matching-part-2

https://www.allaboutcircuits.com/tools/l-match-impedance-matching-circuits/#:~:text=Overview,shape%20(see%20schematic%20below)

https://web.ece.ucsb.edu/~long/ece145a/Notes5_Matching_networks.pdf

Impedance matching network

https://www.youtube.com/watch?v=QsXRhnWI6Co

Playlist for Network Impedance:

https://www.youtube.com/watch?v=TDcad2e3gcA&list=PLP4ZmM6GPueP5KDx3zkRGWmEfbgn G2O35

Three element network:

https://eng.libretexts.org/Bookshelves/Electrical_Engineering/Electronics/Microwave_and_RF_

Design_III_-_Networks_(Steer)/06%3A_Chapter_6/6.6%3A_Multielement_Matching#:~:text=The%20three

%2Delement%20matching%20network,the%20three%2Delement%20matching%20arrangemen

t

L network: https://www.youtube.com/watch?v=Ievioj8lMPs&list=PLQI0-MV8vrBlONj-YXXiwNPYC3lAysWpz&index=2

How to Design RF and Microwave Impedance Matching Networks :

https://www.youtube.com/watch?v=s8oPvj0VLCQ