Robert Boylestad Digital Electronics Copyright ©2002 by Pearson Education, Inc. Upper Saddle River, New Jersey 07458 All rights reserved. Chapter 9: FET.

Slides:



Advertisements
Similar presentations
FET Small-Signal Analysis
Advertisements

Chapter 14 Feedback and Oscillator Circuits
Chapter 5: BJT AC Analysis. Copyright ©2009 by Pearson Education, Inc. Upper Saddle River, New Jersey All rights reserved. Electronic Devices and.
Transistor Amplifiers
FET ( Field Effect Transistor)
FET AND ITS APPLICATIONS UNIT - III 7/2/2015www.noteshit.com1.
Chapter 3: Bipolar Junction Transistors
Chapter 13: Operational Amplifiers
Chapter 7: BJT Transistor Modeling
Chapter 10: Operational Amplifiers. Copyright ©2009 by Pearson Education, Inc. Upper Saddle River, New Jersey All rights reserved. Electronic Devices.
Electronics Principles & Applications Sixth Edition Chapter 7 More About Small-Signal Amplifiers (student version) ©2003 Glencoe/McGraw-Hill Charles A.
© 2012 Pearson Education. Upper Saddle River, NJ, All rights reserved. Electronic Devices, 9th edition Thomas L. Floyd Electronic Devices Ninth.
Storey: Electrical & Electronic Systems © Pearson Education Limited 2004 OHT 20.1 Field-Effect Transistors  Introduction  An Overview of Field-Effect.
Field Effect Transistors Topics Covered in Chapter : JFETs and Their Characteristics 30-2: Biasing Techniques for JFETs 30-3: JFET Amplifiers 30-4:
FET ( Field Effect Transistor)
Week 6 – Chapter 3 FET Small-Signal Analysis Mohd Shawal Jadin FKEE UMP © 2009.
ANALOGUE ELECTRONICS I
12.5 Common Source Amplifiers
Chapter 8: BJT Small-Signal Analysis
Transistors (MOSFETs)
Robert Boylestad Digital Electronics Copyright ©2002 by Pearson Education, Inc. Upper Saddle River, New Jersey All rights reserved. Chapter 11: BJT.
Electronic Devices and Circuit Theory
electronics fundamentals
A.1 Large Signal Operation-Transfer Charact.
Field-Effect Transistors
Chapter 5: Field–Effect Transistors
CHAPTER 7 Junction Field-Effect Transistors. OBJECTIVES Describe and Analyze: JFET theory JFETS vs. Bipolars JFET Characteristics JFET Biasing JFET Circuits.
Chapter 5: BJT AC Analysis
McGraw-Hill © 2008 The McGraw-Hill Companies Inc. All rights reserved. Electronics Principles & Applications Seventh Edition Chapter 7 More About Small-Signal.
7-1 McGraw-Hill Copyright © 2001 by the McGraw-Hill Companies, Inc. All rights reserved. Chapter Seven Frequency Response.
Chapter 11 Op-Amp Applications. Copyright ©2009 by Pearson Education, Inc. Upper Saddle River, New Jersey All rights reserved. Electronic Devices.
Robert Boylestad Digital Electronics Copyright ©2002 by Pearson Education, Inc. Upper Saddle River, New Jersey All rights reserved. Chapter 14: Op-Amp.
Field Effect Transistors By Er. S.GHOSH
Chapter 14: Operational Amplifiers. Copyright ©2009 by Pearson Education, Inc. Upper Saddle River, New Jersey All rights reserved. Electronic Devices.
MOS Field-Effect Transistors (MOSFETs)
Electronic Devices and Circuit Theory
Chapter 4 DC Biasing–BJTs. Copyright ©2009 by Pearson Education, Inc. Upper Saddle River, New Jersey All rights reserved. Electronic Devices and.
Electronic Devices Eighth Edition Floyd Chapter 9.
JFET and MOSFET Amplifiers
FET Amplifiers Chapter 8 Boylestad Electronic Devices and Circuit Theory.
ELECTRICA L ENGINEERING Principles and Applications SECOND EDITION ALLAN R. HAMBLEY ©2002 Prentice-Hall, Inc. Chapter 12 Field-Effect Transistors Chapter.
FET Biasing 1. Introduction For the JFET, the relationship between input and output quantities is nonlinear due to the squared term in Shockley’s equation.
Chapter 7: FET Biasing.
© 2000 Prentice Hall Inc. Figure 5.1 n-Channel enhancement MOSFET showing channel length L and channel width W.
Depletion-type MOSFET bias circuits are similar to JFETs. The only difference is that the depletion-Type MOSFETs can operate with positive values of V.
Basic FET Amplifiers Chapter Six McGraw-Hill
7-1 McGraw-Hill © 2013 The McGraw-Hill Companies, Inc. All rights reserved. Electronics Principles & Applications Eighth Edition Chapter 7 More About Small-Signal.
CHAP3: MOS Field-Effect Transistors (MOSFETs)
FIGURE 7.1 Introducing the reduce and return approach. Robert L. Boylestad Introductory Circuit Analysis, 10ed. Copyright ©2003 by Pearson Education, Inc.
© 2013 The McGraw-Hill Companies, Inc. All rights reserved. McGraw-Hill 7-1 Electronics Principles & Applications Eighth Edition Chapter 7 More About Small-Signal.
Electronics Principles & Applications Fifth Edition Chapter 7 More About Small-Signal Amplifiers ©1999 Glencoe/McGraw-Hill Charles A. Schuler.
Small-Signal FET Amplifier. FET Small-Signal Model FET amplifiers are similar to BJT amplifiers in operation.The purpose of the amplifier is the same.
1 Small Signal Model MOS Field-Effect Transistors (MOSFETs)
Recall Lecture 17 MOSFET DC Analysis 1.Using GS (SG) Loop to calculate V GS Remember that there is NO gate current! 2.Assume in saturation Calculate I.
Chapter 8: FET Amplifiers. Copyright ©2009 by Pearson Education, Inc. Upper Saddle River, New Jersey All rights reserved. Electronic Devices and.
FIGURE 6.1 Parallel elements. Robert L. Boylestad Introductory Circuit Analysis, 10ed. Copyright ©2003 by Pearson Education, Inc. Upper Saddle River, New.
Chapter 4 DC Biasing–BJTs. Copyright ©2009 by Pearson Education, Inc. Upper Saddle River, New Jersey All rights reserved. Electronic Devices and.
SMALL SIGNAL FET (Field– Effect Transistors) AMPLIFIER 1.Introduction/Basic 2.FET Small-Signal Model 3.Fixed-Bias Configuration 4.Self-Bias Configuration.
FET FET’s (Field – Effect Transistors) are much like BJT’s (Bipolar Junction Transistors). Similarities: • Amplifiers • Switching devices • Impedance matching.
Chapter 14 Series and Parallel AC Circuits. Objectives Become familiar with the characteristics of a series and parallel ac circuit Find the total impedance.
TRANSISTORS AND THYRISTORS
Electronics Technology Fundamentals Chapter 21 Field-Effect Transistors and Circuits.
FET AND ITS APPLICATIONS UNIT - III. Field Effect Transistor Family.
Chapter 8: FET Amplifiers
ANALOGUE ELECTRONICS I
FET Amplifiers.
Feedback and Oscillator Circuits
Analog Electronic Circuits 1
Chapter 8: FET Amplifiers
ELECTRONICS AND SOLID STATE DEVICES-II
Presentation transcript:

Robert Boylestad Digital Electronics Copyright ©2002 by Pearson Education, Inc. Upper Saddle River, New Jersey All rights reserved. Chapter 9: FET Small-Signal Analysis

Slide 1 Robert Boylestad Digital Electronics Copyright ©2002 by Pearson Education, Inc. Upper Saddle River, New Jersey All rights reserved. Introduction FETs provide excellent voltage gain high input impedance low-power consumption good frequency range

Slide 2 Robert Boylestad Digital Electronics Copyright ©2002 by Pearson Education, Inc. Upper Saddle River, New Jersey All rights reserved. FET Small-Signal Model Transconductance The relationship of VGS (input) to ID (output) is called transconductance. The transconductance is denoted gm. [Formula 9.2]

Slide 3 Robert Boylestad Digital Electronics Copyright ©2002 by Pearson Education, Inc. Upper Saddle River, New Jersey All rights reserved. Graphical Determination of gm

Slide 4 Robert Boylestad Digital Electronics Copyright ©2002 by Pearson Education, Inc. Upper Saddle River, New Jersey All rights reserved. Mathematical Definition of gm [Formula 9.2] [Formula 9.4] gm for VGS =0V: [Formula 9.5] [Formula 9.6] for [Formula 9.8] [Formula 9.9]

Slide 5 Robert Boylestad Digital Electronics Copyright ©2002 by Pearson Education, Inc. Upper Saddle River, New Jersey All rights reserved. FET Impedance Input Impedance Zi:[Formula 9.10] Output Impedance Zo:[Formula 9.11] [Formula 9.12] yos: admittance equivalent circuit parameter listed on FET specification sheets.

Slide 6 Robert Boylestad Digital Electronics Copyright ©2002 by Pearson Education, Inc. Upper Saddle River, New Jersey All rights reserved. FET AC Equivalent Circuit

Slide 7 Robert Boylestad Digital Electronics Copyright ©2002 by Pearson Education, Inc. Upper Saddle River, New Jersey All rights reserved. JFET Common-Source (CS) Fixed-Bias Configuration The input is on the gate and the output is on the drain.

Slide 8 Robert Boylestad Digital Electronics Copyright ©2002 by Pearson Education, Inc. Upper Saddle River, New Jersey All rights reserved. AC Equivalent Circuit

Slide 9 Robert Boylestad Digital Electronics Copyright ©2002 by Pearson Education, Inc. Upper Saddle River, New Jersey All rights reserved. Impedances Input Impedance: [Formula 9.13] Output Impedance:[Formula 9.14] [Formula 9.15]

Slide 10 Robert Boylestad Digital Electronics Copyright ©2002 by Pearson Education, Inc. Upper Saddle River, New Jersey All rights reserved. Voltage Gain [Formula 9.16] [Formula 9.17]

Slide 11 Robert Boylestad Digital Electronics Copyright ©2002 by Pearson Education, Inc. Upper Saddle River, New Jersey All rights reserved. Phase Relationship A CS amplifier configuration has a 180-degree phase shift between input and output.

Slide 12 Robert Boylestad Digital Electronics Copyright ©2002 by Pearson Education, Inc. Upper Saddle River, New Jersey All rights reserved. JFET CS Self-Bias Configuration This is a CS amplifier configuration therefore the input is on the gate and the output is on the drain.

Slide 13 Robert Boylestad Digital Electronics Copyright ©2002 by Pearson Education, Inc. Upper Saddle River, New Jersey All rights reserved. AC Equivalent Circuit

Slide 14 Robert Boylestad Digital Electronics Copyright ©2002 by Pearson Education, Inc. Upper Saddle River, New Jersey All rights reserved. Impedances Input Impedance: [Formula 9.18] Output Impedance:[Formula 9.19] [Formula 9.20]

Slide 15 Robert Boylestad Digital Electronics Copyright ©2002 by Pearson Education, Inc. Upper Saddle River, New Jersey All rights reserved. Voltage Gain [Formula 9.21] [Formula 9.22]

Slide 16 Robert Boylestad Digital Electronics Copyright ©2002 by Pearson Education, Inc. Upper Saddle River, New Jersey All rights reserved. Phase Relationship A CS amplifier configuration has a 180-degree phase shift between input and output.

Slide 17 Robert Boylestad Digital Electronics Copyright ©2002 by Pearson Education, Inc. Upper Saddle River, New Jersey All rights reserved. JFET CS Self-Bias Configuration – Unbypassed Rs If Cs is removed, it affects the gain of the circuit.

Slide 18 Robert Boylestad Digital Electronics Copyright ©2002 by Pearson Education, Inc. Upper Saddle River, New Jersey All rights reserved. AC Equivalent Circuit

Slide 19 Robert Boylestad Digital Electronics Copyright ©2002 by Pearson Education, Inc. Upper Saddle River, New Jersey All rights reserved. Impedances Input Impedance: [Formula 9.23] Output Impedance: [Formula 9.25(b)]

Slide 20 Robert Boylestad Digital Electronics Copyright ©2002 by Pearson Education, Inc. Upper Saddle River, New Jersey All rights reserved. Voltage Gain [Formula 9.26] [Formula 9.27]

Slide 21 Robert Boylestad Digital Electronics Copyright ©2002 by Pearson Education, Inc. Upper Saddle River, New Jersey All rights reserved. JFET CS Voltage-Divider Configuration This is a CS amplifier configuration therefore the input is on the gate and the output is on the drain.

Slide 22 Robert Boylestad Digital Electronics Copyright ©2002 by Pearson Education, Inc. Upper Saddle River, New Jersey All rights reserved. AC Equivalent Circuit

Slide 23 Robert Boylestad Digital Electronics Copyright ©2002 by Pearson Education, Inc. Upper Saddle River, New Jersey All rights reserved. Impedances Input Impedance: [Formula 9.28] Output Impedance:[Formula 9.29] [Formula 9.30]

Slide 24 Robert Boylestad Digital Electronics Copyright ©2002 by Pearson Education, Inc. Upper Saddle River, New Jersey All rights reserved. Voltage Gain [Formula 9.31] [Formula 9.32]

Slide 25 Robert Boylestad Digital Electronics Copyright ©2002 by Pearson Education, Inc. Upper Saddle River, New Jersey All rights reserved. JFET Source Follower (Common-Drain) Configuration In a CD amplifier configuration the input is on the gate, but the output is from the source.

Slide 26 Robert Boylestad Digital Electronics Copyright ©2002 by Pearson Education, Inc. Upper Saddle River, New Jersey All rights reserved. AC Equivalent Circuit

Slide 27 Robert Boylestad Digital Electronics Copyright ©2002 by Pearson Education, Inc. Upper Saddle River, New Jersey All rights reserved. Impedances Input Impedance: [Formula 9.33] Output Impedance:[Formula 9.34] [Formula 9.35]

Slide 28 Robert Boylestad Digital Electronics Copyright ©2002 by Pearson Education, Inc. Upper Saddle River, New Jersey All rights reserved. Voltage Gain [Formula 9.36] [Formula 9.37]

Slide 29 Robert Boylestad Digital Electronics Copyright ©2002 by Pearson Education, Inc. Upper Saddle River, New Jersey All rights reserved. Phase Relationship A CD amplifier configuration has no phase shift between input and output.

Slide 30 Robert Boylestad Digital Electronics Copyright ©2002 by Pearson Education, Inc. Upper Saddle River, New Jersey All rights reserved. JFET Common-Gate Configuration The input is on source and the output is on the drain.

Slide 31 Robert Boylestad Digital Electronics Copyright ©2002 by Pearson Education, Inc. Upper Saddle River, New Jersey All rights reserved. AC Equivalent Circuit

Slide 32 Robert Boylestad Digital Electronics Copyright ©2002 by Pearson Education, Inc. Upper Saddle River, New Jersey All rights reserved. Impedances Input Impedance: [Formula 9.39] [Formula 9.40] Output Impedance:[Formula 9.41] [Formula 9.42]

Slide 33 Robert Boylestad Digital Electronics Copyright ©2002 by Pearson Education, Inc. Upper Saddle River, New Jersey All rights reserved. Voltage Gain [Formula 9.43] [Formula 9.44]

Slide 34 Robert Boylestad Digital Electronics Copyright ©2002 by Pearson Education, Inc. Upper Saddle River, New Jersey All rights reserved. Phase Relationship A CG amplifier configuration has no phase shift between input and output.

Slide 35 Robert Boylestad Digital Electronics Copyright ©2002 by Pearson Education, Inc. Upper Saddle River, New Jersey All rights reserved. Depletion-Type MOSFETs D-MOSFETs have similar AC equivalent models. The only difference is that V SGQ can be positive for n-channel devices and negative for p-channel devices. This means that gm can be greater than gm0.

Slide 36 Robert Boylestad Digital Electronics Copyright ©2002 by Pearson Education, Inc. Upper Saddle River, New Jersey All rights reserved. D-MOSFET AC Equivalent Model [Fig. 9.34]

Slide 37 Robert Boylestad Digital Electronics Copyright ©2002 by Pearson Education, Inc. Upper Saddle River, New Jersey All rights reserved. Enhancement-Type MOSFETs There are two types of E-MOSFETs: nMOS or n-channel MOSFETs pMOS or p-channel MOSFETs

Slide 38 Robert Boylestad Digital Electronics Copyright ©2002 by Pearson Education, Inc. Upper Saddle River, New Jersey All rights reserved. E-MOSFET AC Equivalent Model gm and rd can be found in the specification sheet for the FET.

Slide 39 Robert Boylestad Digital Electronics Copyright ©2002 by Pearson Education, Inc. Upper Saddle River, New Jersey All rights reserved. E-MOSFET CS Drain-Feedback Configuration

Slide 40 Robert Boylestad Digital Electronics Copyright ©2002 by Pearson Education, Inc. Upper Saddle River, New Jersey All rights reserved. AC Equivalent Circuit

Slide 41 Robert Boylestad Digital Electronics Copyright ©2002 by Pearson Education, Inc. Upper Saddle River, New Jersey All rights reserved. Impedances Input Impedance: [Formula 9.46] [Formula 9.47] Output Impedance:[Formula 9.48] [Formula 9.49]

Slide 42 Robert Boylestad Digital Electronics Copyright ©2002 by Pearson Education, Inc. Upper Saddle River, New Jersey All rights reserved. Voltage Gain [Formula 9.50] [Formula 9.51]

Slide 43 Robert Boylestad Digital Electronics Copyright ©2002 by Pearson Education, Inc. Upper Saddle River, New Jersey All rights reserved. Phase Relationship This is a CS amplifier configuration therefore it has 180-degree phase shift between input and output.

Slide 44 Robert Boylestad Digital Electronics Copyright ©2002 by Pearson Education, Inc. Upper Saddle River, New Jersey All rights reserved. E-MOSFET CS Voltage-Divider Configuration

Slide 45 Robert Boylestad Digital Electronics Copyright ©2002 by Pearson Education, Inc. Upper Saddle River, New Jersey All rights reserved. AC Equivalent Circuit

Slide 46 Robert Boylestad Digital Electronics Copyright ©2002 by Pearson Education, Inc. Upper Saddle River, New Jersey All rights reserved. Impedances Input Impedance: [Formula 9.52] Output Impedance:[Formula 9.53] [Formula 9.54]

Slide 47 Robert Boylestad Digital Electronics Copyright ©2002 by Pearson Education, Inc. Upper Saddle River, New Jersey All rights reserved. Voltage Gain [Formula 9.55] [Formula 9.56]

Slide 48a Robert Boylestad Digital Electronics Copyright ©2002 by Pearson Education, Inc. Upper Saddle River, New Jersey All rights reserved. Summary Table

Slide 48b Robert Boylestad Digital Electronics Copyright ©2002 by Pearson Education, Inc. Upper Saddle River, New Jersey All rights reserved. Summary Table

Slide 49 Robert Boylestad Digital Electronics Copyright ©2002 by Pearson Education, Inc. Upper Saddle River, New Jersey All rights reserved. Troubleshooting 1. Check the DC bias voltages – if not correct check power supply, resistors, FET. Also check to ensure that the coupling capacitor between amplifier stages is OK. 2. Check the AC voltages – if not correct check FET, capacitors and the loading effect of the next stage.

Slide 50 Robert Boylestad Digital Electronics Copyright ©2002 by Pearson Education, Inc. Upper Saddle River, New Jersey All rights reserved. Practical Applications Three-Channel Audio Mixer Silent Switching Phase Shift Networks Motion Detection System