Tweet
Tweet

Slide 1

Slide 1 text

Lecture #5 FET Biasing & AC Analysis Instructor: Dr. Ahmad El-Banna November 2014 J-601-1448 Electronic Principals Integrated Technical Education Cluster At AlAmeeria‎ © Ahmad El-Banna

Slide 2

Slide 2 text

Agenda 2 J-601-1448 , Lec#5 , Nov 2014 © Ahmad El-Banna Construction and Characteristics FET Biasing Design and Troubleshooting JFET small signal Model FET Amplifier Networks Practical Applications Note! Same concepts of the BJT, so we will just overview the FET transistors.

Slide 3

Slide 3 text

CONSTRUCTION AND CHARACTERISTICS 3 J-601-1448 , Lec#5 , Nov 2014 © Ahmad El-Banna

Slide 4

Slide 4 text

Construction 4 J-601-1448 , Lec#5 , Nov 2014 © Ahmad El-Banna • One of the most important characteristics of the FET is its high input impedance. • FETs are more temperature stable than BJTs, and FETs are usually smaller than BJTs, making them particularly useful in integrated-circuit (IC) chips.

Slide 5

Slide 5 text

Construction.. 5 J-601-1448 , Lec#5 , Nov 2014 © Ahmad El-Banna N-channel

Slide 6

Slide 6 text

Characteristics & Equations 6 J-601-1448 , Lec#5 , Nov 2014 © Ahmad El-Banna

Slide 7

Slide 7 text

Depletion-Type MOSFET 7 J-601-1448 , Lec#5 , Nov 2014 © Ahmad El-Banna • There is no direct electrical connection between the gate terminal and the channel of a MOSFET. • It is the insulating layer of SiO2 in the MOSFET construction that accounts for the very desirable high input impedance of the device.

Slide 8

Slide 8 text

Depletion-Type MOSFET 8 J-601-1448 , Lec#5 , Nov 2014 © Ahmad El-Banna

Slide 9

Slide 9 text

Other MOSFETS 9 J-601-1448 , Lec#5 , Nov 2014 © Ahmad El-Banna • VMOS AND UMOS POWER MOSFETs • CMOS • MESFET

Slide 10

Slide 10 text

FET BIASING 10 J-601-1448 , Lec#5 , Nov 2014 © Ahmad El-Banna

Slide 11

Slide 11 text

FIXED-BIAS CONFIGURATION 11 J-601-1448 , Lec#5 , Nov 2014 © Ahmad El-Banna

Slide 12

Slide 12 text

Example 12 J-601-1448 , Lec#5 , Nov 2014 © Ahmad El-Banna

Slide 13

Slide 13 text

Voltage-Divider Bias 13 J-601-1448 , Lec#5 , Nov 2014 © Ahmad El-Banna

Slide 14

Slide 14 text

Example 14 J-601-1448 , Lec#5 , Nov 2014 © Ahmad El-Banna

Slide 15

Slide 15 text

DESIGN AND TROUBLESHOOTING 15 J-601-1448 , Lec#5 , Nov 2014 © Ahmad El-Banna

Slide 16

Slide 16 text

Design Example 16 J-601-1448 , Lec#5 , Nov 2014 © Ahmad El-Banna

Slide 17

Slide 17 text

Troubleshooting 17 J-601-1448 , Lec#5 , Nov 2014 © Ahmad El-Banna The level of VDS is typically between 25% and 75% of VDD . The continuity of a network can be checked simply by measuring the voltage across any resistor of the network.

Slide 18

Slide 18 text

JFET SMALL SIGNAL MODEL 18 J-601-1448 , Lec#5 , Nov 2014 © Ahmad El-Banna

Slide 19

Slide 19 text

JFET small signal Model 19 J-601-1448 , Lec#5 , Nov 2014 © Ahmad El-Banna

Slide 20

Slide 20 text

Fixed-Bias Configuration 20 J-601-1448 , Lec#5 , Nov 2014 © Ahmad El-Banna phase shift of 180° between input and output voltages.

Slide 21

Slide 21 text

VOLTAGE-DIVIDER CONFIGURATION 21 J-601-1448 , Lec#5 , Nov 2014 © Ahmad El-Banna

Slide 22

Slide 22 text

FET AMPLIFIER NETWORKS 22 J-601-1448 , Lec#5 , Nov 2014 © Ahmad El-Banna

Slide 23

Slide 23 text

Design FET Amplifier Network 23 J-601-1448 , Lec#5 , Nov 2014 © Ahmad El-Banna

Slide 24

Slide 24 text

24 J-601-1448 , Lec#5 , Nov 2014 © Ahmad El-Banna Summary Table

Slide 25

Slide 25 text

25 J-601-1448 , Lec#5 , Nov 2014 © Ahmad El-Banna

Slide 26

Slide 26 text

Cascaded Configuration 26 J-601-1448 , Lec#5 , Nov 2014 © Ahmad El-Banna

Slide 27

Slide 27 text

PRACTICAL APPLICATIONS 27 J-601-1448 , Lec#5 , Nov 2014 © Ahmad El-Banna

Slide 28

Slide 28 text

Three-Channel Audio Mixer 28 J-601-1448 , Lec#5 , Nov 2014 © Ahmad El-Banna

Slide 29

Slide 29 text

Motion Detection System 29 J-601-1448 , Lec#5 , Nov 2014 © Ahmad El-Banna

Slide 30

Slide 30 text

• For more details, refer to: • Chapter 6,7,8, Electronic Devices and Circuits, Boylestad. • The lecture is available online at: • https://speakerdeck.com/ahmad_elbanna • For inquires, send to: • ahmad.elbanna@feng.bu.edu.eg 30 J-601-1448 , Lec#5 , Nov 2014 © Ahmad El-Banna