Download presentation

Presentation is loading. Please wait.

Published byAntwan Gloster Modified over 2 years ago

1
ELECTRICAL ENGINEERING: PRINCIPLES AND APPLICATIONS, Fourth Edition, by Allan R. Hambley, ©2008 Pearson Education, Inc. Lecture 28 Field-Effect Transistors

2
ELECTRICAL ENGINEERING: PRINCIPLES AND APPLICATIONS, Fourth Edition, by Allan R. Hambley, ©2008 Pearson Education, Inc. Field-Effect Transistors 1.Understand MOSFET operation. 2. Analyze basic FET amplifiers using the load- line technique. 3. Analyze bias circuits.

3
ELECTRICAL ENGINEERING: PRINCIPLES AND APPLICATIONS, Fourth Edition, by Allan R. Hambley, ©2008 Pearson Education, Inc. 4. Use small-signal equivalent circuits to analyze FET amplifiers. 5. Compute the performance parameters of several FET amplifier configurations. 7. Understand the basic operation of CMOS logic gates.

4
ELECTRICAL ENGINEERING: PRINCIPLES AND APPLICATIONS, Fourth Edition, by Allan R. Hambley, ©2008 Pearson Education, Inc. NMOS Transistor

5
ELECTRICAL ENGINEERING: PRINCIPLES AND APPLICATIONS, Fourth Edition, by Allan R. Hambley, ©2008 Pearson Education, Inc. NMOS Transistor

6
ELECTRICAL ENGINEERING: PRINCIPLES AND APPLICATIONS, Fourth Edition, by Allan R. Hambley, ©2008 Pearson Education, Inc. Operation in the Cutoff Region

7
ELECTRICAL ENGINEERING: PRINCIPLES AND APPLICATIONS, Fourth Edition, by Allan R. Hambley, ©2008 Pearson Education, Inc. Operation Slightly Above Cut-Off By applying a positive bias between the Gate (G) and the body (B), electrons are attracted to the gate to form a conducting n-type channel between the source and drain. The positive charge on the gate and the negative charge in the channel form a capacitor where:

8
ELECTRICAL ENGINEERING: PRINCIPLES AND APPLICATIONS, Fourth Edition, by Allan R. Hambley, ©2008 Pearson Education, Inc. The amount of negative charge that accumulates in the channel is given by: This amount of charge is able to move a distance L from the source to the drain in a time given by: Operation Slightly Above Cut-Off

9
ELECTRICAL ENGINEERING: PRINCIPLES AND APPLICATIONS, Fourth Edition, by Allan R. Hambley, ©2008 Pearson Education, Inc. The initial current flow for low drain-source voltage is given by: Operation Slightly Above Cut-Off

10
ELECTRICAL ENGINEERING: PRINCIPLES AND APPLICATIONS, Fourth Edition, by Allan R. Hambley, ©2008 Pearson Education, Inc. Operation Slightly Above Cut-Off For small values of v DS, i D is proportional to v DS. The device behaves as a resistance whose value depends on v GS.

11
ELECTRICAL ENGINEERING: PRINCIPLES AND APPLICATIONS, Fourth Edition, by Allan R. Hambley, ©2008 Pearson Education, Inc. Operation in the Triode Region

12
ELECTRICAL ENGINEERING: PRINCIPLES AND APPLICATIONS, Fourth Edition, by Allan R. Hambley, ©2008 Pearson Education, Inc. Operation in the Saturation Region

13
ELECTRICAL ENGINEERING: PRINCIPLES AND APPLICATIONS, Fourth Edition, by Allan R. Hambley, ©2008 Pearson Education, Inc.

14
Exercise 12.1 Consider an NMOS transistor having V to =2V. What is the region of operation (triode, saturation, or cutoff) if: 1. v GS = 1V and v DS = 5V? Cutoff since v GS

15
ELECTRICAL ENGINEERING: PRINCIPLES AND APPLICATIONS, Fourth Edition, by Allan R. Hambley, ©2008 Pearson Education, Inc. Exercise 12.2 Suppose that we have an NMOS transistor with KP = 50 A/V 2, V to = 1V, L = 2 m and W = 80 m. Sketch the drain characteristics for v DS from 0 to 10V and v GS =0, 1, 2, 3 and 4V. For v GS = 0 or 1V, the transistor is cutoff and the drain current is zero. In the saturation region: The boundary between the triode and saturation regions occurs when

16
ELECTRICAL ENGINEERING: PRINCIPLES AND APPLICATIONS, Fourth Edition, by Allan R. Hambley, ©2008 Pearson Education, Inc. Exercise 12.2

17
ELECTRICAL ENGINEERING: PRINCIPLES AND APPLICATIONS, Fourth Edition, by Allan R. Hambley, ©2008 Pearson Education, Inc. PMOS Transistor p+ n

18
ELECTRICAL ENGINEERING: PRINCIPLES AND APPLICATIONS, Fourth Edition, by Allan R. Hambley, ©2008 Pearson Education, Inc. MOSFET Summary

19
ELECTRICAL ENGINEERING: PRINCIPLES AND APPLICATIONS, Fourth Edition, by Allan R. Hambley, ©2008 Pearson Education, Inc. Exercise 12.3 Suppose that we have an PMOS transistor with KP = 25 A/V 2, V to = -1V, L = 2 m and W = 200 m. Sketch the drain characteristics for v DS from 0 to -10V and v GS = 0, -1, -2, -3 and -4V. For v GS = 0 or -1V, the transistor is cutoff and the drain current is zero. In the saturation region: The boundary between the triode and saturation regions occurs when

20
ELECTRICAL ENGINEERING: PRINCIPLES AND APPLICATIONS, Fourth Edition, by Allan R. Hambley, ©2008 Pearson Education, Inc. Exercise 12.3

21
ELECTRICAL ENGINEERING: PRINCIPLES AND APPLICATIONS, Fourth Edition, by Allan R. Hambley, ©2008 Pearson Education, Inc. Load-Line Analysis of a Simple NMOS Circuit

22
ELECTRICAL ENGINEERING: PRINCIPLES AND APPLICATIONS, Fourth Edition, by Allan R. Hambley, ©2008 Pearson Education, Inc. To establish the load line, we first locate two points on it: Load-Line Analysis of a Simple NMOS Circuit For v DD = 20V and R D =1k

23
ELECTRICAL ENGINEERING: PRINCIPLES AND APPLICATIONS, Fourth Edition, by Allan R. Hambley, ©2008 Pearson Education, Inc. Load-Line Analysis of a Simple NMOS Circuit

24
ELECTRICAL ENGINEERING: PRINCIPLES AND APPLICATIONS, Fourth Edition, by Allan R. Hambley, ©2008 Pearson Education, Inc. Load-Line Analysis of a Simple NMOS Circuit The quiescent operating point (Q point) is found for v in = 0V

25
ELECTRICAL ENGINEERING: PRINCIPLES AND APPLICATIONS, Fourth Edition, by Allan R. Hambley, ©2008 Pearson Education, Inc. Load-Line Analysis of a Simple NMOS Circuit The maximum gate-to-source voltage is found for v in = 1V

26
ELECTRICAL ENGINEERING: PRINCIPLES AND APPLICATIONS, Fourth Edition, by Allan R. Hambley, ©2008 Pearson Education, Inc. Load-Line Analysis of a Simple NMOS Circuit The minimum gate-to-source voltage is found for v in = -1V

27
ELECTRICAL ENGINEERING: PRINCIPLES AND APPLICATIONS, Fourth Edition, by Allan R. Hambley, ©2008 Pearson Education, Inc. Load-Line Analysis of a Simple NMOS Circuit

28
ELECTRICAL ENGINEERING: PRINCIPLES AND APPLICATIONS, Fourth Edition, by Allan R. Hambley, ©2008 Pearson Education, Inc. Peak to peak swing of v GS is 2V Peak to peak swing of v DS is 12V

29
ELECTRICAL ENGINEERING: PRINCIPLES AND APPLICATIONS, Fourth Edition, by Allan R. Hambley, ©2008 Pearson Education, Inc. The output is not proportional to the input. The output goes down by 7V for a change of +1V on the input. The output goes up by 5V for a change of -1V on the input. The output is said to be “distorted”. This is due to the uneven spacing of the characteristic curves. v DSQ =11V +5V -7V

30
ELECTRICAL ENGINEERING: PRINCIPLES AND APPLICATIONS, Fourth Edition, by Allan R. Hambley, ©2008 Pearson Education, Inc. Load-Line Analysis of a Simple NMOS Circuit Uneven spacing of the drain characteristics

31
ELECTRICAL ENGINEERING: PRINCIPLES AND APPLICATIONS, Fourth Edition, by Allan R. Hambley, ©2008 Pearson Education, Inc. Exercise 12.4 Find v DSQ, v DSmin and v DSmax if the circuit values are changed to V DD =15V, V GG =3V: 3V 15V

32
ELECTRICAL ENGINEERING: PRINCIPLES AND APPLICATIONS, Fourth Edition, by Allan R. Hambley, ©2008 Pearson Education, Inc. To establish the load line, we first locate two points on it: For v DD = 15V and R D =1k Exercise 12.4

33
ELECTRICAL ENGINEERING: PRINCIPLES AND APPLICATIONS, Fourth Edition, by Allan R. Hambley, ©2008 Pearson Education, Inc. Exercise 12.4 v DSQ =11V v DSmin =6Vv DSmax =14V

34
ELECTRICAL ENGINEERING: PRINCIPLES AND APPLICATIONS, Fourth Edition, by Allan R. Hambley, ©2008 Pearson Education, Inc. FET Logic

35
ELECTRICAL ENGINEERING: PRINCIPLES AND APPLICATIONS, Fourth Edition, by Allan R. Hambley, ©2008 Pearson Education, Inc. CMOS Inverter

36
ELECTRICAL ENGINEERING: PRINCIPLES AND APPLICATIONS, Fourth Edition, by Allan R. Hambley, ©2008 Pearson Education, Inc. Two-Input CMOS NAND Gate

37
ELECTRICAL ENGINEERING: PRINCIPLES AND APPLICATIONS, Fourth Edition, by Allan R. Hambley, ©2008 Pearson Education, Inc. Two-Input CMOS NOR Gate

38
ELECTRICAL ENGINEERING: PRINCIPLES AND APPLICATIONS, Fourth Edition, by Allan R. Hambley, ©2008 Pearson Education, Inc.

Similar presentations

OK

ELECTRICAL ENGINEERING: PRINCIPLES AND APPLICATIONS, Fourth Edition, by Allan R. Hambley, ©2008 Pearson Education, Inc. Lecture 27 Bipolar Junction Transistors.

ELECTRICAL ENGINEERING: PRINCIPLES AND APPLICATIONS, Fourth Edition, by Allan R. Hambley, ©2008 Pearson Education, Inc. Lecture 27 Bipolar Junction Transistors.

© 2018 SlidePlayer.com Inc.

All rights reserved.

Ads by Google

Ppt on shell scripting youtube Ppt on ip addressing and subnetting Ppt on tunnel diodes Ppt on ip address classes and range Job based pay ppt online Ppt on eye os Ppt on road accidents pictures Ppt on agriculture insurance in india Ppt on do's and don'ts of group discussion activities Ppt on vitamin deficiency diseases