1. EENG 3520: Electronics II
Lecture 1
Oluwayomi Adamo

2. Course Outline Chapter 1, 2, 4, 6: Review
Chapter 7: Single Stage Integrated Circuit Amplifiers
Chapter 8: Differential and Multistage Amplifiers
Chapter 10: Feedback
Chapter 11: Output Stages and Power Amplifers
Chapter 13: Digital CMOS Logic Circuits

3. Course Announcement In class Email: oluwayomi.adamo@unt.edu Web:
Office Hour:
Mon.: 2:00 – 4:00 PM (B208)

4. Grading Policy In-class Quiz (10%) Homework (20%) Project (15%)
Midterm (25%)
Final (30%)

5. 1. Frequency Response of Amplifiers
Fourier transform: to obtain frequency spectrum of a signal whose waveform is an arbitrary function of time

6. 1. Frequency Response of Amplifiers
1.6.1 Measuring the amplifier frequency response
The input signal to an amplifier can be expressed as the sum of sinusoidal signals
An amplifier can be characterized by the response to input sinusoids of different frequencies
Input and output:
Same frequency
Amplitude Response:
Phase Response:

7. 1. Frequency Response of Amplifiers
1.6.2 Amplifier Bandwidth
Amax
A3dB
Bandwidth = 2 - 1

8. 1. Frequency Response of Amplifiers
1.6.3 Evaluating the frequency response of amplifiers
Component
Impedance
Resistor (R) R
Inductor (L)
jL, sL
Capacitor (C)
1/ jC, 1/sC

9. 1. Frequency Response of Amplifiers
1.6.4 Single-Time-Constant Networks
STC: Composed of, or can be reduce to one reactive component (inductance or capacitance) and one resistance.

10. 1. Frequency Response of Amplifiers
1.6.4 Single-Time-Constant Networks (cont.)
cut-off Frequency
Bode Plot
passband
stopband
Hendrik Wade Bode (1905 – 1982)
Figure (a) Magnitude and (b) phase response of STC networks of the low-pass type.

11. 1. Frequency Response of Amplifiers
1.6.4 Single-Time-Constant Networks (cont.)
Bode Plot
Figure (a) Magnitude and (b) phase response of STC networks of the high-pass type.

12. 2. Operational Amplifiers
2.1 Characteristics of the Ideal Op-amp
Infinite input impedance
Zero output impedance
Zero common-mode gain or equivalent, infinite common-mode rejection
Infinite bandwidth
Infinite open-loop gain A

13. 2. Operational Amplifiers
2.2 The Closed-Loop Gain
Step 1: Virtual short circuit
Tracking each other in potential
Not physically shorting terminals 1 and 2
Step 4: Ideal Op-amp has an infinite input
impedance and draws ZERO current

14. 2. Operational Amplifiers
2.3 Superposition Law
REMOVE SOURCES
Superimpose

15. 3. Diode
3.1 Introduction
Physical Structure
Symbol

16. 3. Diode
3.2 Ideal Diode
Fig The ideal diode: (a) diode circuit symbol; (b) i-v characteristic; (c) equivalent circuit in the reverse direction; (d) equivalent circuit in the forward direction.

17. 3. Diode
3.3 Diode Regions

18. Homework
1.66, 1.67, D2.50, 4.18, 4.26, 6.12, 6.39, 6.59