Prof. Paolo Colantonio a.a

Size: px
Start display at page:

Download "Prof. Paolo Colantonio a.a"

Transcription

1 Prof. Paolo Colantonio a.a. 20 2

2 Field effect transistors (FETs) are probably the simplest form of transistor, widely used in both analogue and digital applications They are characterised by a very high input resistance and small physical size, and they can be used to form circuits with a low power consumption They are widely used in ery Large Scale Integration (LSI) There are two basic forms: insulated gate FETs junction gate FETs Many forms, but basic operation is the same a voltage on a control input produces an electric field that affects the current between two other terminals when considering amplifiers we looked at a circuit using a control device a FET is a suitable control device o IR The current I is controlled by the input signal i Thus the output signal o is controlled by the input signal i If an appropriate gain is given by the control device, it behaves like a voltage amplifier Prof. Paolo Colantonio 2 24

3 FETs are 3 terminal devices drain (d) source (s) gate (g) The gate is the control input oltages are given symbols of the form XX, where X and Y correspond to the symbols of two of the device s terminals (example GS ) Currents are given symbols of the form I Z, where Z correspond to the device associated terminal (example I D ) Upper case letters used for steady quantities GS or I D Lower case letters for varying quantities v gs or i d Special notation for power supply voltage or current, by doubling the subscript associated to the device terminal DD, SS, I DD, I SS Prof. Paolo Colantonio 3 24

4 Such devices are sometimes called IGFETs (insulated gate field effect transistors) or sometimes MOSFETs (metal oxide semiconductor field effect transistors) Digital circuits constructed using these devices are usually described as using MOS technology Here we will describe them as MOSFETs These devices are realized in either n channel or p channel semiconductor material Prof. Paolo Colantonio 4 24

5 An n channel device is formed by taking a p type semiconductor (the substrate, namely bulk, b) and forming n type regions within it to represent the drain and source pads Electrical connections are made to these regions to form the drain and source electrodes A thin n type channel is then formed to join these two regions (the channel) This channel is covered by an insulating oxide layer and then by a metal gate electrode Electrical connections are made to the gate an substrate Usually the substrate is internally connected to the source to form a three terminal device (i.e. with only three external connections) Prof. Paolo Colantonio 5 24

6 Gate voltage controls the thickness of the channel Consider an n channel device making the gate more positive attracts electrons to the gate and makes the channel thicker reducing the resistance of the channel. The channel is said to be enhanced making the gate more negative repels electrons from the gate and makes the channel thinner increasing the resistance of the channel. The channel is said to be depleted Prof. Paolo Colantonio 6 24

7 Devices as described above are termed depletion enhancement MOSFETs or simply DE MOSFETs Some MOSFETs are constructed so that in the absence of any gate voltage there is no channel Such devices can be operated in an enhancement mode, but not in a depletion mode (since there is no channel to deplete) These are called Enhancement MOSFETs Both forms of MOSFET are available as either n channel or p channel devices Prof. Paolo Colantonio 7 24

8 Sometimes known as a JUGFET, most often with the common name JFET As in a MOSFET, conduction takes place through a channel formed in a semiconductor material Here the insulated gate of a MOSFET is replaced with a reverse biased pn junction Since the gate junction is always reverse biased no current flows into the gate and it acts as if it were insulated Prof. Paolo Colantonio 8 24

9 The reverse biased gate junction produces a depletion layer in the region of the channel The gate volt controls the thickness of the depletion layer and hence the thickness of the channel Consider an n channel device the gate will always be negative with respect to the source to keep the junction between the gate and the channel reverse biased making the gate more negative increases the thickness of the depletion layer, reducing the width of the channel increasing the resistance of the channel Prof. Paolo Colantonio 9 24

10 The arrow shows the polarity of the device It points towards and n type channel or away from in a p type channel Prof. Paolo Colantonio 0 24

11 While MOSFETs and JFETs operate in different ways, their characteristics are quite similar Input characteristics in both MOSFETs and JFETs the gate is effectively insulated from the remainder of the device Output characteristics consider n channel devices usually the drain is more positive than the source the drain voltage affects the thickness of the channel Prof. Paolo Colantonio 24

12 The applied voltage DS produces a drain current I D through the channel between the drain and the source Such a current produces a potential drop due to the channel resistance The potential gradually falls along the channel The thickness of the channel is mainly controlled by the voltage applied to the gate but it is also influenced by the drain to source voltage Prof. Paolo Colantonio 2 24

13 For small values of DS, the behavior of the channel resembles that of a resistor, with the drain current I D being proportional to the drain voltage DS The value of this effective resistance is controlled by the gate voltage GS It decreases as GS is made more positive This is referred as the ohmic region of the device s operation As DS is increased the channel becomes more tapered and it thickness is reduced to approximately zero at the end near the channel The channel in this situation is said to be pinched off and the value of DS is called pinch off voltage This does not stop the flow of current, while preventing its any further increase This is referred to as the saturation region of the device s operation Prof. Paolo Colantonio 3 24

14 If GS is kept constant, while increasing DS the current I D initially rises (almost) linearly with the applied voltage (ohmic region) then above the pinch off voltage becomes essentially constant (saturation region) arying GS, the effective resistance of the channel in the ohmic region and also the value of the steady current is changed Prof. Paolo Colantonio 4 24

15 The DE MOSFETs are used with both positive and negative gate voltages, while MOSFETs use only one polarity (positive GS for n channel type, NMOS, negative for p type, PMOS) The gate voltage at which the device starts to conduct is called threshold voltage T For n type DE MOSFET it will have a negative value of a few volts For enhancement MOS a positive value of a few volts at pinch off DS GS T I D [ma] Locus of pinch-off = - DS GS T GS =+2 GS =+ Enhancement I D [ma] Locus of pinch-off = - DS GS T GS =+9 GS =+8 I DSS GS =0 GS =- GS =-2 GS =-3 GS =-4 GS =-5 = [] DS T Depletion GS =+7 GS =+6 GS =+5 GS =+4 GS =+3 GS [] DS =+2 = T Prof. Paolo Colantonio 5 24

16 The output characteristic of a JFET are similar to those of MOSFETs, except that the useful range of GS is different The drain current produced for GS=0 is termed the drain to source saturation current IDSS The gate voltage at which the channel stops conducting is now called pinch off voltage P at pinch off DS GS P I DSS I D [ma] Locus of pinch-off = - DS GS P GS =0 GS =- GS =-2 GS =-3 GS =-4 GS =-5 GS =-6 [] DS GS P Prof. Paolo Colantonio 6 24 =-7 =

17 It represents the relationship between the input voltage GS and the output current I D Obviously there is no linear relationship between GS and I D However, if the device remains within the saturation region, it is possible to plot such relationship Similar shape for all forms of FET but with a different offset I D I D I D DE NMOS NMOS JFET I DSS I DSS T GS T GS P GS 2 I K D GS T I D IDSS Which can be rearranged into the form GS P 2 2 I K' D GS P Prof. Paolo Colantonio 7 24

18 The relationship between the input voltage GS and the output current I D does not show a linear response, but over a small region might be considered to approximate a linear response DE N MOS N MOS N JFET When operating about its operating point the transfer characteristic can be described by its slope This quantity has units of current/voltage, which is the reciprocal of resistance (that is conductance) It is called the transconductance, g m ID did i I d D gm d v GS GS gs GS Prof. Paolo Colantonio 8 24

19 In a real FET, in the saturation region the current I D slightly increase with DS I D [ma] Locus of pinch-off = - DS GS T GS -/ [] DS The slope of the I curve in the saturation region represents a resistance r d Prolonging the characteristic in the saturation region towards left, all of them cross in the same point at DS = /, usually referred as Early s voltage Typical values of are between 0.0 and I K D GS T DS Prof. Paolo Colantonio 9 24

20 The transconductance g m is proportional to the square root of the drain current MOSFET JFET di D gm 2KGS T d GS I D 2K 2 K I K D g m di 2 D GS IDSS dgs P P 2 I I D DSS I DSS 2 P I DSS P The small signal equivalent circuit models the behaviour of the device for small variations of the input about the operating point I D r d is given by the slope of the output characteristic and, for this reason, is also known as the output slope resistance Prof. Paolo Colantonio 20 24

21 At high frequencies more sophisticated models are used The gate and the channel in a MOSFET are separated by an insulator, resembling a capacitor In a JFET, the insulator is replaced by a depletion layer, which has the same effect In both case capacitances are present between the gate and the channel As the channel is joined to the drain at one end and to the source at the other, capacitance is present between the gate and each of the other terminals The reverse biased junction between drain and substrate also acts as a capacitor Since the substrate is normally joined to the source, it results in a capacitance between drain and source Prof. Paolo Colantonio 2 24

22 Consider the case A, where an impedance Z is connected between two points of a network characterised by a voltage gain K It is possible to make the electrical transformation as case B The two networks must have the same voltages at the external nodes A I Z I 2 B A= / 2 2 Z I A = / 2 I 2 Z 2 2 I 2 A Z Z I Z Z Z A I A Z Z I 2 Z 2 2 Z A A Z2 Z A Prof. Paolo Colantonio 22 24

23 It is possible to consider a dual effect The two networks must have the same mesh currents A A=-I/ I 2 I 2 B Z Z 2 A=-I/ I 2 I 2 N 2N 2 N 2N 2 I N I 2 I N I 2 Z Z I I Z I A N 2 N I Z I N Z Z A I 2 2N ZI I22N ZI2 A I Z I 2 2N 2 2 AI Z2 Z Z AI AI Prof. Paolo Colantonio 23 24

24 Considering the Miller effect Z Z A A Z2 Z A A C C A gd gd A C C C A gd gd gd C gd C A gd C C A gd gd C C C A T gs gd C C C out ds gd Prof. Paolo Colantonio 24 24

Analogue Electronics

Analogue Electronics Università degli Studi di Roma Tor Vergata Dipartimento di Ingegneria Elettronica Analogue Electronics Paolo Colantonio A.A. 2015-16 Field-effect transistors Field-effect transistors (FETs) are probably

More information

Basic Electronics Prof. Dr. Chitralekha Mahanta Department of Electronics and Communication Engineering Indian Institute of Technology, Guwahati

Basic Electronics Prof. Dr. Chitralekha Mahanta Department of Electronics and Communication Engineering Indian Institute of Technology, Guwahati Basic Electronics Prof. Dr. Chitralekha Mahanta Department of Electronics and Communication Engineering Indian Institute of Technology, Guwahati Module: 3 Field Effect Transistors Lecture-7 High Frequency

More information

UNIT 3: FIELD EFFECT TRANSISTORS

UNIT 3: FIELD EFFECT TRANSISTORS FIELD EFFECT TRANSISTOR: UNIT 3: FIELD EFFECT TRANSISTORS The field effect transistor is a semiconductor device, which depends for its operation on the control of current by an electric field. There are

More information

Depletion-mode operation ( 공핍형 ): Using an input gate voltage to effectively decrease the channel size of an FET

Depletion-mode operation ( 공핍형 ): Using an input gate voltage to effectively decrease the channel size of an FET Ch. 13 MOSFET Metal-Oxide-Semiconductor Field-Effect Transistor : I D D-mode E-mode V g The gate oxide is made of dielectric SiO 2 with e = 3.9 Depletion-mode operation ( 공핍형 ): Using an input gate voltage

More information

MEASUREMENT AND INSTRUMENTATION STUDY NOTES UNIT-I

MEASUREMENT AND INSTRUMENTATION STUDY NOTES UNIT-I MEASUREMENT AND INSTRUMENTATION STUDY NOTES The MOSFET The MOSFET Metal Oxide FET UNIT-I As well as the Junction Field Effect Transistor (JFET), there is another type of Field Effect Transistor available

More information

Field Effect Transistors

Field Effect Transistors Field Effect Transistors LECTURE NO. - 41 Field Effect Transistors www.mycsvtunotes.in JFET MOSFET CMOS Field Effect transistors - FETs First, why are we using still another transistor? BJTs had a small

More information

INTRODUCTION TO MOS TECHNOLOGY

INTRODUCTION TO MOS TECHNOLOGY INTRODUCTION TO MOS TECHNOLOGY 1. The MOS transistor The most basic element in the design of a large scale integrated circuit is the transistor. For the processes we will discuss, the type of transistor

More information

UNIT-VI FIELD EFFECT TRANSISTOR. 1. Explain about the Field Effect Transistor and also mention types of FET s.

UNIT-VI FIELD EFFECT TRANSISTOR. 1. Explain about the Field Effect Transistor and also mention types of FET s. UNIT-I FIELD EFFECT TRANSISTOR 1. Explain about the Field Effect Transistor and also mention types of FET s. The Field Effect Transistor, or simply FET however, uses the voltage that is applied to their

More information

Three Terminal Devices

Three Terminal Devices Three Terminal Devices - field effect transistor (FET) - bipolar junction transistor (BJT) - foundation on which modern electronics is built - active devices - devices described completely by considering

More information

Chapter 6: Field-Effect Transistors

Chapter 6: Field-Effect Transistors Chapter 6: Field-Effect Transistors Islamic University of Gaza Dr. Talal Skaik MOSFETs MOSFETs have characteristics similar to JFETs and additional characteristics that make then very useful. There are

More information

COLLECTOR DRAIN BASE GATE EMITTER. Applying a voltage to the Gate connection allows current to flow between the Drain and Source connections.

COLLECTOR DRAIN BASE GATE EMITTER. Applying a voltage to the Gate connection allows current to flow between the Drain and Source connections. MOSFETS Although the base current in a transistor is usually small (< 0.1 ma), some input devices (e.g. a crystal microphone) may be limited in their output. In order to overcome this, a Field Effect Transistor

More information

Field-Effect Transistor (FET) is one of the two major transistors; FET derives its name from its working mechanism;

Field-Effect Transistor (FET) is one of the two major transistors; FET derives its name from its working mechanism; Chapter 3 Field-Effect Transistors (FETs) 3.1 Introduction Field-Effect Transistor (FET) is one of the two major transistors; FET derives its name from its working mechanism; The concept has been known

More information

EE70 - Intro. Electronics

EE70 - Intro. Electronics EE70 - Intro. Electronics Course website: ~/classes/ee70/fall05 Today s class agenda (November 28, 2005) review Serial/parallel resonant circuits Diode Field Effect Transistor (FET) f 0 = Qs = Qs = 1 2π

More information

Electronic Circuits. Junction Field-effect Transistors. Dr. Manar Mohaisen Office: F208 Department of EECE

Electronic Circuits. Junction Field-effect Transistors. Dr. Manar Mohaisen Office: F208   Department of EECE Electronic Circuits Junction Field-effect Transistors Dr. Manar Mohaisen Office: F208 Email: manar.subhi@kut.ac.kr Department of EECE Review of the Precedent Lecture Explain the Operation Class A Power

More information

FET. Field Effect Transistors ELEKTRONIKA KONTROL. Eka Maulana, ST, MT, M.Eng. Universitas Brawijaya. p + S n n-channel. Gate. Basic structure.

FET. Field Effect Transistors ELEKTRONIKA KONTROL. Eka Maulana, ST, MT, M.Eng. Universitas Brawijaya. p + S n n-channel. Gate. Basic structure. FET Field Effect Transistors ELEKTRONIKA KONTROL Basic structure Gate G Source S n n-channel Cross section p + p + p + G Depletion region Drain D Eka Maulana, ST, MT, M.Eng. Universitas Brawijaya S Channel

More information

IENGINEERS-CONSULTANTS QUESTION BANK SERIES ELECTRONICS ENGINEERING 1 YEAR UPTU ELECTRONICS ENGINEERING EC 101 UNIT 3 (JFET AND MOSFET)

IENGINEERS-CONSULTANTS QUESTION BANK SERIES ELECTRONICS ENGINEERING 1 YEAR UPTU ELECTRONICS ENGINEERING EC 101 UNIT 3 (JFET AND MOSFET) ELECTRONICS ENGINEERING EC 101 UNIT 3 (JFET AND MOSFET) LONG QUESTIONS (10 MARKS) 1. Draw the construction diagram and explain the working of P-Channel JFET. Also draw the characteristics curve and transfer

More information

Basic Electronics Prof. Dr. Chitralekha Mahanta Department of Electronics and Communication Engineering Indian Institute of Technology, Guwahati

Basic Electronics Prof. Dr. Chitralekha Mahanta Department of Electronics and Communication Engineering Indian Institute of Technology, Guwahati Basic Electronics Prof. Dr. Chitralekha Mahanta Department of Electronics and Communication Engineering Indian Institute of Technology, Guwahati Module: 3 Field Effect Transistors Lecture-8 Junction Field

More information

8. Characteristics of Field Effect Transistor (MOSFET)

8. Characteristics of Field Effect Transistor (MOSFET) 1 8. Characteristics of Field Effect Transistor (MOSFET) 8.1. Objectives The purpose of this experiment is to measure input and output characteristics of n-channel and p- channel field effect transistors

More information

CHAPTER 8 FIELD EFFECT TRANSISTOR (FETs)

CHAPTER 8 FIELD EFFECT TRANSISTOR (FETs) CHAPTER 8 FIELD EFFECT TRANSISTOR (FETs) INTRODUCTION - FETs are voltage controlled devices as opposed to BJT which are current controlled. - There are two types of FETs. o Junction FET (JFET) o Metal

More information

Chapter 8. Field Effect Transistor

Chapter 8. Field Effect Transistor Chapter 8. Field Effect Transistor Field Effect Transistor: The field effect transistor is a semiconductor device, which depends for its operation on the control of current by an electric field. There

More information

Q1. Explain the construction and principle of operation of N-Channel and P-Channel Junction Field Effect Transistor (JFET).

Q1. Explain the construction and principle of operation of N-Channel and P-Channel Junction Field Effect Transistor (JFET). Q. Explain the construction and principle of operation of N-Channel and P-Channel Junction Field Effect Transistor (JFET). Answer: N-Channel Junction Field Effect Transistor (JFET) Construction: Drain(D)

More information

IFB270 Advanced Electronic Circuits

IFB270 Advanced Electronic Circuits IFB270 Advanced Electronic Circuits Chapter 9: FET amplifiers and switching circuits Prof. Manar Mohaisen Department of EEC Engineering Review of the Precedent Lecture Review of basic electronic devices

More information

Digital Electronics. By: FARHAD FARADJI, Ph.D. Assistant Professor, Electrical and Computer Engineering, K. N. Toosi University of Technology

Digital Electronics. By: FARHAD FARADJI, Ph.D. Assistant Professor, Electrical and Computer Engineering, K. N. Toosi University of Technology K. N. Toosi University of Technology Chapter 7. Field-Effect Transistors By: FARHAD FARADJI, Ph.D. Assistant Professor, Electrical and Computer Engineering, K. N. Toosi University of Technology http://wp.kntu.ac.ir/faradji/digitalelectronics.htm

More information

Chapter 5: Field Effect Transistors

Chapter 5: Field Effect Transistors Chapter 5: Field Effect Transistors Slide 1 FET FET s (Field Effect Transistors) are much like BJT s (Bipolar Junction Transistors). Similarities: Amplifiers Switching devices Impedance matching circuits

More information

FET(Field Effect Transistor)

FET(Field Effect Transistor) Field Effect Transistor: Construction and Characteristic of JFETs. Transfer Characteristic. CS,CD,CG amplifier and analysis of CS amplifier MOSFET (Depletion and Enhancement) Type, Transfer Characteristic,

More information

Introduction to MOSFET MOSFET (Metal Oxide Semiconductor Field Effect Transistor)

Introduction to MOSFET MOSFET (Metal Oxide Semiconductor Field Effect Transistor) Microelectronic Circuits Introduction to MOSFET MOSFET (Metal Oxide Semiconductor Field Effect Transistor) Slide 1 MOSFET Construction MOSFET (Metal Oxide Semiconductor Field Effect Transistor) Slide 2

More information

Field Effect Transistors

Field Effect Transistors Chapter 5: Field Effect Transistors Slide 1 FET FET s (Field Effect Transistors) are much like BJT s (Bipolar Junction Transistors). Similarities: Amplifiers Switching devices Impedance matching circuits

More information

Lecture 16: MOS Transistor models: Linear models, SPICE models. Context. In the last lecture, we discussed the MOS transistor, and

Lecture 16: MOS Transistor models: Linear models, SPICE models. Context. In the last lecture, we discussed the MOS transistor, and Lecture 16: MOS Transistor models: Linear models, SPICE models Context In the last lecture, we discussed the MOS transistor, and added a correction due to the changing depletion region, called the body

More information

UNIT-1 Bipolar Junction Transistors. Text Book:, Microelectronic Circuits 6 ed., by Sedra and Smith, Oxford Press

UNIT-1 Bipolar Junction Transistors. Text Book:, Microelectronic Circuits 6 ed., by Sedra and Smith, Oxford Press UNIT-1 Bipolar Junction Transistors Text Book:, Microelectronic Circuits 6 ed., by Sedra and Smith, Oxford Press Figure 6.1 A simplified structure of the npn transistor. Microelectronic Circuits, Sixth

More information

INTRODUCTION: Basic operating principle of a MOSFET:

INTRODUCTION: Basic operating principle of a MOSFET: INTRODUCTION: Along with the Junction Field Effect Transistor (JFET), there is another type of Field Effect Transistor available whose Gate input is electrically insulated from the main current carrying

More information

Questions on JFET: 1) Which of the following component is a unipolar device?

Questions on JFET: 1) Which of the following component is a unipolar device? Questions on JFET: 1) Which of the following component is a unipolar device? a) BJT b) FET c) DJT d) EFT 2) Current Conduction in FET takes place due e) Majority charge carriers only f) Minority charge

More information

Electronic Circuits II - Revision

Electronic Circuits II - Revision Electronic Circuits II - Revision -1 / 16 - T & F # 1 A bypass capacitor in a CE amplifier decreases the voltage gain. 2 If RC in a CE amplifier is increased, the voltage gain is reduced. 3 4 5 The load

More information

Conduction Characteristics of MOS Transistors (for fixed Vds)! Topic 2. Basic MOS theory & SPICE simulation. MOS Transistor

Conduction Characteristics of MOS Transistors (for fixed Vds)! Topic 2. Basic MOS theory & SPICE simulation. MOS Transistor Conduction Characteristics of MOS Transistors (for fixed Vds)! Topic 2 Basic MOS theory & SPICE simulation Peter Cheung Department of Electrical & Electronic Engineering Imperial College London (Weste&Harris,

More information

Topic 2. Basic MOS theory & SPICE simulation

Topic 2. Basic MOS theory & SPICE simulation Topic 2 Basic MOS theory & SPICE simulation Peter Cheung Department of Electrical & Electronic Engineering Imperial College London (Weste&Harris, Ch 2 & 5.1-5.3 Rabaey, Ch 3) URL: www.ee.ic.ac.uk/pcheung/

More information

Conduction Characteristics of MOS Transistors (for fixed Vds) Topic 2. Basic MOS theory & SPICE simulation. MOS Transistor

Conduction Characteristics of MOS Transistors (for fixed Vds) Topic 2. Basic MOS theory & SPICE simulation. MOS Transistor Conduction Characteristics of MOS Transistors (for fixed Vds) Topic 2 Basic MOS theory & SPICE simulation Peter Cheung Department of Electrical & Electronic Engineering Imperial College London (Weste&Harris,

More information

EDC UNIT IV- Transistor and FET JFET Characteristics EDC Lesson 4- ", Raj Kamal, 1

EDC UNIT IV- Transistor and FET JFET Characteristics EDC Lesson 4- , Raj Kamal, 1 EDC UNIT IV- Transistor and FET Characteristics Lesson-10: JFET Characteristics Qualitative Discussion 2008 EDC Lesson 4- ", Raj Kamal, 1 n-junction FET and p-jfet Symbols D D + D G + V DS V DS V GS S

More information

Electronic Circuits for Mechatronics ELCT 609 Lecture 6: MOS-FET Transistor

Electronic Circuits for Mechatronics ELCT 609 Lecture 6: MOS-FET Transistor Electronic Circuits for Mechatronics ELCT 609 Lecture 6: MOS-FET Transistor Assistant Professor Office: C3.315 E-mail: eman.azab@guc.edu.eg 1 Introduction Why we call it Transistor? The name came as an

More information

ITT Technical Institute. ET215 Devices 1. Unit 7 Chapter 4, Sections

ITT Technical Institute. ET215 Devices 1. Unit 7 Chapter 4, Sections ITT Technical Institute ET215 Devices 1 Unit 7 Chapter 4, Sections 4.1 4.3 Chapter 4 Section 4.1 Structure of Field-Effect Transistors Recall that the BJT is a current-controlling device; the field-effect

More information

Summary. Electronics II Lecture 5(b): Metal-Oxide Si FET MOSFET. A/Lectr. Khalid Shakir Dept. Of Electrical Engineering

Summary. Electronics II Lecture 5(b): Metal-Oxide Si FET MOSFET. A/Lectr. Khalid Shakir Dept. Of Electrical Engineering Summary Electronics II Lecture 5(b): Metal-Oxide Si FET MOSFET A/Lectr. Khalid Shakir Dept. Of Electrical Engineering College of Engineering Maysan University Page 1-21 Summary The MOSFET The metal oxide

More information

MODULE-2: Field Effect Transistors (FET)

MODULE-2: Field Effect Transistors (FET) FORMAT-1B Definition: MODULE-2: Field Effect Transistors (FET) FET is a three terminal electronic device used for variety of applications that match with BJT. In FET, an electric field is established by

More information

Chapter 6: Field-Effect Transistors

Chapter 6: Field-Effect Transistors Chapter 6: Field-Effect Transistors FETs vs. BJTs Similarities: Amplifiers Switching devices Impedance matching circuits Differences: FETs are voltage controlled devices. BJTs are current controlled devices.

More information

ITT Technical Institute. ET215 Devices 1. Unit 8 Chapter 4, Sections

ITT Technical Institute. ET215 Devices 1. Unit 8 Chapter 4, Sections ITT Technical Institute ET215 Devices 1 Unit 8 Chapter 4, Sections 4.4 4.5 Chapter 4 Section 4.4 MOSFET Characteristics A Metal-Oxide semiconductor field-effect transistor is the other major category of

More information

Field Effect Transistors (npn)

Field Effect Transistors (npn) Field Effect Transistors (npn) gate drain source FET 3 terminal device channel e - current from source to drain controlled by the electric field generated by the gate base collector emitter BJT 3 terminal

More information

Design cycle for MEMS

Design cycle for MEMS Design cycle for MEMS Design cycle for ICs IC Process Selection nmos CMOS BiCMOS ECL for logic for I/O and driver circuit for critical high speed parts of the system The Real Estate of a Wafer MOS Transistor

More information

FIELD EFFECT TRANSISTOR (FET) 1. JUNCTION FIELD EFFECT TRANSISTOR (JFET)

FIELD EFFECT TRANSISTOR (FET) 1. JUNCTION FIELD EFFECT TRANSISTOR (JFET) FIELD EFFECT TRANSISTOR (FET) The field-effect transistor (FET) is a three-terminal device used for a variety of applications that match, to a large extent, those of the BJT transistor. Although there

More information

Analog Electronics. Electronic Devices, 9th edition Thomas L. Floyd Pearson Education. Upper Saddle River, NJ, All rights reserved.

Analog Electronics. Electronic Devices, 9th edition Thomas L. Floyd Pearson Education. Upper Saddle River, NJ, All rights reserved. Analog Electronics BJT Structure The BJT has three regions called the emitter, base, and collector. Between the regions are junctions as indicated. The base is a thin lightly doped region compared to the

More information

KOM2751 Analog Electronics :: Dr. Muharrem Mercimek :: YTU - Control and Automation Dept. 1 6 FIELD-EFFECT TRANSISTORS

KOM2751 Analog Electronics :: Dr. Muharrem Mercimek :: YTU - Control and Automation Dept. 1 6 FIELD-EFFECT TRANSISTORS KOM2751 Analog Electronics :: Dr. Muharrem Mercimek :: YTU - Control and Automation Dept. 1 6 FIELD-EFFECT TRANSISTORS Most of the content is from the textbook: Electronic devices and circuit theory, Robert

More information

Gechstudentszone.wordpress.com

Gechstudentszone.wordpress.com UNIT 4: Small Signal Analysis of Amplifiers 4.1 Basic FET Amplifiers In the last chapter, we described the operation of the FET, in particular the MOSFET, and analyzed and designed the dc response of circuits

More information

MOSFET Terminals. The voltage applied to the GATE terminal determines whether current can flow between the SOURCE & DRAIN terminals.

MOSFET Terminals. The voltage applied to the GATE terminal determines whether current can flow between the SOURCE & DRAIN terminals. MOSFET Terminals The voltage applied to the GATE terminal determines whether current can flow between the SOURCE & DRAIN terminals. For an n-channel MOSFET, the SOURCE is biased at a lower potential (often

More information

L MOSFETS, IDENTIFICATION, CURVES. PAGE 1. I. Review of JFET (DRAW symbol for n-channel type, with grounded source)

L MOSFETS, IDENTIFICATION, CURVES. PAGE 1. I. Review of JFET (DRAW symbol for n-channel type, with grounded source) L.107.4 MOSFETS, IDENTIFICATION, CURVES. PAGE 1 I. Review of JFET (DRAW symbol for n-channel type, with grounded source) 1. "normally on" device A. current from source to drain when V G = 0 no need to

More information

Exam Below are two schematics of current sources implemented with MOSFETs. Which current source has the best compliance voltage?

Exam Below are two schematics of current sources implemented with MOSFETs. Which current source has the best compliance voltage? Exam 2 Name: Score /90 Question 1 Short Takes 1 point each unless noted otherwise. 1. Below are two schematics of current sources implemented with MOSFETs. Which current source has the best compliance

More information

Field - Effect Transistor

Field - Effect Transistor Page 1 of 6 Field - Effect Transistor Aim :- To draw and study the out put and transfer characteristics of the given FET and to determine its parameters. Apparatus :- FET, two variable power supplies,

More information

6. Field-Effect Transistor

6. Field-Effect Transistor 6. Outline: Introduction to three types of FET: JFET MOSFET & CMOS MESFET Constructions, Characteristics & Transfer curves of: JFET & MOSFET Introduction The field-effect transistor (FET) is a threeterminal

More information

FET. FET (field-effect transistor) JFET. Prepared by Engr. JP Timola Reference: Electronic Devices by Floyd

FET. FET (field-effect transistor) JFET. Prepared by Engr. JP Timola Reference: Electronic Devices by Floyd FET Prepared by Engr. JP Timola Reference: Electronic Devices by Floyd FET (field-effect transistor) unipolar devices - unlike BJTs that use both electron and hole current, they operate only with one type

More information

Unit III FET and its Applications. 2 Marks Questions and Answers

Unit III FET and its Applications. 2 Marks Questions and Answers Unit III FET and its Applications 2 Marks Questions and Answers 1. Why do you call FET as field effect transistor? The name field effect is derived from the fact that the current is controlled by an electric

More information

Metal-Oxide-Silicon (MOS) devices PMOS. n-type

Metal-Oxide-Silicon (MOS) devices PMOS. n-type Metal-Oxide-Silicon (MOS devices Principle of MOS Field Effect Transistor transistor operation Metal (poly gate on oxide between source and drain Source and drain implants of opposite type to substrate.

More information

Physics 364, Fall 2012, reading due your answers to by 11pm on Thursday

Physics 364, Fall 2012, reading due your answers to by 11pm on Thursday Physics 364, Fall 2012, reading due 2012-10-25. Email your answers to ashmansk@hep.upenn.edu by 11pm on Thursday Course materials and schedule are at http://positron.hep.upenn.edu/p364 Assignment: (a)

More information

The Common Source JFET Amplifier

The Common Source JFET Amplifier The Common Source JFET Amplifier Small signal amplifiers can also be made using Field Effect Transistors or FET's for short. These devices have the advantage over bipolar transistors of having an extremely

More information

EIE209 Basic Electronics. Transistor Devices. Contents BJT and FET Characteristics Operations. Prof. C.K. Tse: T ransistor devices

EIE209 Basic Electronics. Transistor Devices. Contents BJT and FET Characteristics Operations. Prof. C.K. Tse: T ransistor devices EIE209 Basic Electronics Transistor Devices Contents BJT and FET Characteristics Operations 1 What is a transistor? Three-terminal device whose voltage-current relationship is controlled by a third voltage

More information

EDC UNIT IV- Transistor and FET Characteristics EDC Lesson 9- ", Raj Kamal, 1

EDC UNIT IV- Transistor and FET Characteristics EDC Lesson 9- , Raj Kamal, 1 EDC UNIT IV- Transistor and FET Characteristics Lesson-9: JFET and Construction of JFET 2008 EDC Lesson 9- ", Raj Kamal, 1 1. Transistor 2008 EDC Lesson 9- ", Raj Kamal, 2 Transistor Definition The transferred-resistance

More information

Field-Effect Transistor

Field-Effect Transistor Philadelphia University Faculty of Engineering Communication and Electronics Engineering Field-Effect Transistor Introduction FETs (Field-Effect Transistors) are much like BJTs (Bipolar Junction Transistors).

More information

(Refer Slide Time: 02:05)

(Refer Slide Time: 02:05) Electronics for Analog Signal Processing - I Prof. K. Radhakrishna Rao Department of Electrical Engineering Indian Institute of Technology Madras Lecture 27 Construction of a MOSFET (Refer Slide Time:

More information

Lecture - 18 Transistors

Lecture - 18 Transistors Electronic Materials, Devices and Fabrication Dr. S. Prarasuraman Department of Metallurgical and Materials Engineering Indian Institute of Technology, Madras Lecture - 18 Transistors Last couple of classes

More information

ECE520 VLSI Design. Lecture 2: Basic MOS Physics. Payman Zarkesh-Ha

ECE520 VLSI Design. Lecture 2: Basic MOS Physics. Payman Zarkesh-Ha ECE520 VLSI Design Lecture 2: Basic MOS Physics Payman Zarkesh-Ha Office: ECE Bldg. 230B Office hours: Wednesday 2:00-3:00PM or by appointment E-mail: pzarkesh@unm.edu Slide: 1 Review of Last Lecture Semiconductor

More information

THE JFET. Script. Discuss the JFET and how it differs from the BJT. Describe the basic structure of n-channel and p -channel JFETs

THE JFET. Script. Discuss the JFET and how it differs from the BJT. Describe the basic structure of n-channel and p -channel JFETs Course: B.Sc. Applied Physical Science (Computer Science) Year & Sem.: Ist Year, Sem - IInd Subject: Electronics Paper No.: V Paper Title: Analog Circuits Lecture No.: 12 Lecture Title: Analog Circuits

More information

UNIT 3 Transistors JFET

UNIT 3 Transistors JFET UNIT 3 Transistors JFET Mosfet Definition of BJT A bipolar junction transistor is a three terminal semiconductor device consisting of two p-n junctions which is able to amplify or magnify a signal. It

More information

Figure 1: JFET common-source amplifier. A v = V ds V gs

Figure 1: JFET common-source amplifier. A v = V ds V gs Chapter 7: FET Amplifiers Switching and Circuits The Common-Source Amplifier In a common-source (CS) amplifier, the input signal is applied to the gate and the output signal is taken from the drain. The

More information

Lecture (10) MOSFET. By: Dr. Ahmed ElShafee. Dr. Ahmed ElShafee, ACU : Fall 2016, Electronic Circuits II

Lecture (10) MOSFET. By: Dr. Ahmed ElShafee. Dr. Ahmed ElShafee, ACU : Fall 2016, Electronic Circuits II Lecture (10) MOSFET By: Dr. Ahmed ElShafee ١ Dr. Ahmed ElShafee, ACU : Fall 2017, Electronic Circuits II Introduction The MOSFET (metal oxide semiconductor field effect transistor) is another category

More information

UNIT II JFET, MOSFET, SCR & UJT

UNIT II JFET, MOSFET, SCR & UJT UNIT II JFET, MOSFET, SCR & UJT JFET JFET as an Amplifier and its Output Characteristics JFET Applications MOSFET Working Principles, SCR Equivalent Circuit and V-I Characteristics. SCR as a Half wave

More information

Radio Frequency Electronics

Radio Frequency Electronics Radio Frequency Electronics Active Components II Harry Nyquist Born in 1889 in Sweden Received B.S. and M.S. from U. North Dakota Received Ph.D. from Yale Worked and Bell Laboratories for all of his career

More information

I E I C since I B is very small

I E I C since I B is very small Figure 2: Symbols and nomenclature of a (a) npn and (b) pnp transistor. The BJT consists of three regions, emitter, base, and collector. The emitter and collector are usually of one type of doping, while

More information

PESIT Bangalore South Campus

PESIT Bangalore South Campus INTERNAL ASSESSMENT TEST 2 Date : 19/09/2016 Max Marks: 40 Subject & Code : Analog and Digital Electronics (15CS32) Section: III A and B Name of faculty: Deepti.C Time : 8:30 am-10:00 am Note: Answer five

More information

55:041 Electronic Circuits

55:041 Electronic Circuits 55:041 Electronic Circuits MOSFETs Sections of Chapter 3 &4 A. Kruger MOSFETs, Page-1 Basic Structure of MOS Capacitor Sect. 3.1 Width = 1 10-6 m or less Thickness = 50 10-9 m or less ` MOS Metal-Oxide-Semiconductor

More information

Field-Effect Transistors

Field-Effect Transistors R L 2 Field-Effect Transistors 2.1 BAIC PRINCIPLE OF JFET The eld-effect transistor (FET) is an electric- eld (voltage) operated transistor, developed as a semiconductor equivalent of the vacuum-tube device,

More information

FIELD EFFECT TRANSISTORS MADE BY : GROUP (13)/PM

FIELD EFFECT TRANSISTORS MADE BY : GROUP (13)/PM FIELD EFFECT TRANSISTORS MADE BY : GROUP (13)/PM THE FIELD EFFECT TRANSISTOR (FET) In 1945, Shockley had an idea for making a solid state device out of semiconductors. He reasoned that a strong electrical

More information

BJT Amplifier. Superposition principle (linear amplifier)

BJT Amplifier. Superposition principle (linear amplifier) BJT Amplifier Two types analysis DC analysis Applied DC voltage source AC analysis Time varying signal source Superposition principle (linear amplifier) The response of a linear amplifier circuit excited

More information

55:041 Electronic Circuits

55:041 Electronic Circuits 55:041 Electronic Circuits Mosfet Review Sections of Chapter 3 &4 A. Kruger Mosfet Review, Page-1 Basic Structure of MOS Capacitor Sect. 3.1 Width 1 10-6 m or less Thickness 50 10-9 m or less ` MOS Metal-Oxide-Semiconductor

More information

Prof. Paolo Colantonio a.a

Prof. Paolo Colantonio a.a Prof. Paolo olantonio a.a. 2011 12 ipolar transistors are one of the main building blocks in electronic systems They are used in both analogue and digital circuits They incorporate two pn junctions and

More information

EE105 Fall 2015 Microelectronic Devices and Circuits: MOSFET Prof. Ming C. Wu 511 Sutardja Dai Hall (SDH)

EE105 Fall 2015 Microelectronic Devices and Circuits: MOSFET Prof. Ming C. Wu 511 Sutardja Dai Hall (SDH) EE105 Fall 2015 Microelectronic Devices and Circuits: MOSFET Prof. Ming C. Wu wu@eecs.berkeley.edu 511 Sutardja Dai Hall (SDH) 7-1 Simplest Model of MOSFET (from EE16B) 7-2 CMOS Inverter 7-3 CMOS NAND

More information

Semiconductor Physics and Devices

Semiconductor Physics and Devices Metal-Semiconductor and Semiconductor Heterojunctions The Metal-Oxide-Semiconductor Field-Effect Transistor (MOSFET) is one of two major types of transistors. The MOSFET is used in digital circuit, because

More information

Difference between BJTs and FETs. Junction Field Effect Transistors (JFET)

Difference between BJTs and FETs. Junction Field Effect Transistors (JFET) Difference between BJTs and FETs Transistors can be categorized according to their structure, and two of the more commonly known transistor structures, are the BJT and FET. The comparison between BJTs

More information

ECE 340 Lecture 40 : MOSFET I

ECE 340 Lecture 40 : MOSFET I ECE 340 Lecture 40 : MOSFET I Class Outline: MOS Capacitance-Voltage Analysis MOSFET - Output Characteristics MOSFET - Transfer Characteristics Things you should know when you leave Key Questions How do

More information

Transistor Characteristics

Transistor Characteristics Transistor Characteristics Introduction Transistors are the most recent additions to a family of electronic current flow control devices. They differ from diodes in that the level of current that can flow

More information

Field Effect Transistors

Field Effect Transistors Field Effect Transistors Purpose In this experiment we introduce field effect transistors (FETs). We will measure the output characteristics of a FET, and then construct a common-source amplifier stage,

More information

Chapter 4. CMOS Cascode Amplifiers. 4.1 Introduction. 4.2 CMOS Cascode Amplifiers

Chapter 4. CMOS Cascode Amplifiers. 4.1 Introduction. 4.2 CMOS Cascode Amplifiers Chapter 4 CMOS Cascode Amplifiers 4.1 Introduction A single stage CMOS amplifier cannot give desired dc voltage gain, output resistance and transconductance. The voltage gain can be made to attain higher

More information

An introduction to Depletion-mode MOSFETs By Linden Harrison

An introduction to Depletion-mode MOSFETs By Linden Harrison An introduction to Depletion-mode MOSFETs By Linden Harrison Since the mid-nineteen seventies the enhancement-mode MOSFET has been the subject of almost continuous global research, development, and refinement

More information

Analog Electronic Circuits Prof. S. C. Dutta Roy Department of Electrical Engineering Indian Institute of Technology Delhi Lecture No 03

Analog Electronic Circuits Prof. S. C. Dutta Roy Department of Electrical Engineering Indian Institute of Technology Delhi Lecture No 03 Analog Electronic Circuits Prof. S. C. Dutta Roy Department of Electrical Engineering Indian Institute of Technology Delhi Lecture No 03 Before we take FETs let us recall and example which we had taken

More information

Electronic PRINCIPLES

Electronic PRINCIPLES MALVINO & BATES Electronic PRINCIPLES SEVENTH EDITION Chapter 13 JFETs Topics Covered in Chapter 13 Basic ideas Drain curves Transconductance curve Biasing in the ohmic region Biasing in the active region

More information

4.2.2 Metal Oxide Semiconductor Field Effect Transistor (MOSFET)

4.2.2 Metal Oxide Semiconductor Field Effect Transistor (MOSFET) 4.2.2 Metal Oxide Semiconductor Field Effect Transistor (MOSFET) The Metal Oxide Semitonductor Field Effect Transistor (MOSFET) has two modes of operation, the depletion mode, and the enhancement mode.

More information

ET Training. Electronics: JFET Instructor: H.Pham. The JUNCTION FIELF EFFECT TRANSISTOR (JFET) n channel JFET p channel JFET

ET Training. Electronics: JFET Instructor: H.Pham. The JUNCTION FIELF EFFECT TRANSISTOR (JFET) n channel JFET p channel JFET The JUNCTION FIELF EFFECT TRANSISTOR (JFET) n channel JFET p channel JFET 1 The BIASED JFET VDD provides a drain-to-source voltage and supplies current from drain to source VGG sets the reverse-biased

More information

ECE 340 Lecture 37 : Metal- Insulator-Semiconductor FET Class Outline:

ECE 340 Lecture 37 : Metal- Insulator-Semiconductor FET Class Outline: ECE 340 Lecture 37 : Metal- Insulator-Semiconductor FET Class Outline: Metal-Semiconductor Junctions MOSFET Basic Operation MOS Capacitor Things you should know when you leave Key Questions What is the

More information

Digital Electronics Part II - Circuits

Digital Electronics Part II - Circuits Digital Electronics Part II - Circuits Dr. I. J. Wassell Gates from Transistors 1 Introduction Logic circuits are non-linear, consequently we will introduce a graphical technique for analysing such circuits

More information

MOSFET & IC Basics - GATE Problems (Part - I)

MOSFET & IC Basics - GATE Problems (Part - I) MOSFET & IC Basics - GATE Problems (Part - I) 1. Channel current is reduced on application of a more positive voltage to the GATE of the depletion mode n channel MOSFET. (True/False) [GATE 1994: 1 Mark]

More information

4.1 Device Structure and Physical Operation

4.1 Device Structure and Physical Operation 10/12/2004 4_1 Device Structure and Physical Operation blank.doc 1/2 4.1 Device Structure and Physical Operation Reading Assignment: pp. 235-248 Chapter 4 covers Field Effect Transistors ( ) Specifically,

More information

Chapter 4 Single-stage MOS amplifiers

Chapter 4 Single-stage MOS amplifiers Chapter 4 Single-stage MOS amplifiers ELEC-H402/CH4: Single-stage MOS amplifiers 1 Single-stage MOS amplifiers NMOS as an amplifier: example of common-source circuit NMOS amplifier example Introduction

More information

Field-Effect Transistor

Field-Effect Transistor Module: Electronics Module Number: 610/6501- Philadelphia University Faculty of Engineering Communication and Electronics Engineering Field-Effect Transistor ntroduction FETs (Field-Effect Transistors)

More information

Experiment#: 8. The JFET Characteristics & DC Biasing. Electronics (I) Laboratory. The Hashemite University. Faculty of Engineering

Experiment#: 8. The JFET Characteristics & DC Biasing. Electronics (I) Laboratory. The Hashemite University. Faculty of Engineering The Hashemite University Faculty of Engineering Department of Electrical and Computer Engineering Electronics (I) Laboratory Experiment#: 8 The JFET Characteristics & DC Biasing Student s Name : Ja'afar

More information

INTRODUCTION TO ELECTRONICS EHB 222E

INTRODUCTION TO ELECTRONICS EHB 222E INTRODUCTION TO ELECTRONICS EHB 222E MOS Field Effect Transistors (MOSFETS II) MOSFETS 1/ INTRODUCTION TO ELECTRONICS 1 MOSFETS Amplifiers Cut off when v GS < V t v DS decreases starting point A, once

More information

Lecture (03) The JFET

Lecture (03) The JFET Lecture (03) The JFET By: Dr. Ahmed ElShafee ١ JFET Basic Structure Figure shows the basic structure of an n channel JFET (junction field effect transistor). Wire leads are connected to each end of the

More information

Lecture-45. MOS Field-Effect-Transistors Threshold voltage

Lecture-45. MOS Field-Effect-Transistors Threshold voltage Lecture-45 MOS Field-Effect-Transistors 7.4. Threshold voltage In this section we summarize the calculation of the threshold voltage and discuss the dependence of the threshold voltage on the bias applied

More information