Chapter 1 - Introduction to Electronics Introduction Microelectronics Integrated Circuits (IC) Technology Silicon Chip Microcomputer / Microprocessor Discrete Circuits

Signals Signal Processing Transducers

Signals Voltage Sources Current Sources Thevenin & Norton

Figure 1.1 Two alternative representations of a signal source: (a) the Thévenin form, and (b) the Norton form.

Figure 1.2 An arbitrary voltage signal v s (t).

Figure 1.3 Sine-wave voltage signal of amplitude V a and frequency f = 1/T Hz. The angular frequency v = 2 p f rad/s.

Signals Voltage Sources Current Sources

Signals Voltage Sources Current Sources

Frequency Spectrum of Signals Fourier Series Fourier Transform Fundamental and Harmonics frequency time

Figure 1.4 A symmetrical square-wave signal of amplitude V.

Figure 1.5 The frequency spectrum (also known as the line spectrum) of the periodic square wave of Fig. 1.4.

Figure 1.6 The frequency spectrum of an arbitrary waveform such as that in Fig. 1.2.

Figure 1.7 Sampling the continuous-time analog signal in (a) results in the discrete-time signal in (b).

Frequency Spectrum of Signals Fourier Series

Frequency Spectrum of Signals Fourier Series

Frequency Spectrum of Signals Fourier Series

Frequency Spectrum of Signals Fourier Series

Frequency Spectrum of Signals Fourier Series

Frequency Spectrum of Signals Fourier Series

Frequency Spectrum of Signals

Frequency Spectrum of Signals

Figure 1.8 Variation of a particular binary digital signal with time.

Figure 1.9 Block-diagram representation of the analog-to-digital converter (ADC).

Analog and Digital Signals Sampling Rate Binary number system Analog-to-Digital Converter Digital-to-Analog Converter

Figure 1.10 (a) Circuit symbol for amplifier. (b) An amplifier with a common terminal (ground) between the input and output ports.

Figure 1.11 (a) A voltage amplifier fed with a signal v I (t) and connected to a load resistance R L. (b) Transfer characteristic of a linear voltage amplifier with voltage gain A v.

Figure 1.12 An amplifier that requires two dc supplies (shown as batteries) for operation.

Figure 1.13 An amplifier transfer characteristic that is linear except for output saturation.

Figure 1.14 (a) An amplifier transfer characteristic that shows considerable nonlinearity. (b) To obtain linear operation the amplifier is biased as shown, and the signal amplitude is kept small. Observe that this amplifier is operated from a single power supply, V DD.

Figure 1.15 A sketch of the transfer characteristic of the amplifier of Example 1.2. Note that this amplifier is inverting (i.e., with a gain that is negative).

Figure 1.16 Symbol convention employed throughout the book.

Figure 1.17 (a) Circuit model for the voltage amplifier. (b) The voltage amplifier with input signal source and load.

Figure 1.18 Three-stage amplifier for Example 1.3.

Figure 1.19 (a) Small-signal circuit model for a bipolar junction transistor (BJT). (b) The BJT connected as an amplifier with the emitter as a common terminal between input and output (called a common-emitter amplifier). (c) An alternative small-signal circuit model for the BJT.

Figure E1.20

Figure 1.20 Measuring the frequency response of a linear amplifier. At the test frequency v, the amplifier gain is characterized by its magnitude (V o /V i ) and phase f.

Figure 1.21 Typical magnitude response of an amplifier. |T( v )| is the magnitude of the amplifier transfer function—that is, the ratio of the output V o ( v ) to the input V i ( v ).

Figure 1.22 Two examples of STC networks: (a) a low-pass network and (b) a high-pass network.

Figure 1.23 (a) Magnitude and (b) phase response of STC networks of the low-pass type.

Figure 1.24 (a) Magnitude and (b) phase response of STC networks of the high-pass type.

Figure 1.25 Circuit for Example 1.5.

Figure 1.26 Frequency response for (a) a capacitively coupled amplifier, (b) a direct-coupled amplifier, and (c) a tuned or bandpass amplifier.

Figure 1.27 Use of a capacitor to couple amplifier stages.

Figure E1.23

Figure 1.28 A logic inverter operating from a dc supply V DD.

Figure 1.29 Voltage transfer characteristic of an inverter. The VTC is approximated by three straightline segments. Note the four parameters of the VTC (V OH, V OL, V IL, and V IH ) and their use in determining the noise margins (NM H and NM L ).

Figure 1.30 The VTC of an ideal inverter.

Figure 1.31 (a) The simplest implementation of a logic inverter using a voltage-controlled switch; (b) equivalent circuit when v I is low; and (c) equivalent circuit when v I is high. Note that the switch is assumed to close when v I is high.

Figure 1.32 A more elaborate implementation of the logic inverter utilizing two complementary switches. This is the basis of the CMOS inverter studied in Section 4.10.

Figure 1.33 Another inverter implementation utilizing a double-throw switch to steer the constant current I EE to R C1 (when v I is high) or R C2 (when v I is low). This is the basis of the emitter-coupled logic (ECL) studied in Chapters 7 and 11.

Figure 1.34 Example 1.6: (a) The inverter circuit after the switch opens (i.e., for t  0  ). (b) Waveforms of v I and v O. Observe that the switch is assumed to operate instantaneously. v O rises exponentially, starting at V OL and heading toward V OH.

Figure 1.35 Definitions of propagation delays and transition times of the logic inverter.

Figure P1.6

Figure P1.10

Figure P1.14

Figure P1.15

Figure P1.16

Figure P1.17

Figure P1.18

Figure P1.37

Figure P1.58

Figure P1.63

Figure P1.65

Figure P1.67

Figure P1.68

Figure P1.72

Figure P1.77

Figure P1.79

Table 1.1 The Four Amplifier Types

VinVout Voltage gain (A v ) = V out /V in Linear - output is proportional to input Amplifiers Current amplifierscurrent gain (A i ) = I out /I in Power amplifierspower gain (A p ) = P out /P in

Amplifiers Signal Amplification Distortion Non-Linear Distortion Symbols Gains – Voltage, Power, Current Decibels Amplifier Power Supplies Efficiency

Gain in terms of decibels Typical values of voltage gain, 10, 100, 1000 depending on size of input signal Decibels often used when dealing with large ranges or multiple stages A v in decibels (dB) = 20log|A v | A i in decibels (dB) = 20log|A i | A p in decibels (dB) = 10log|A p | Amplifiers Av = log|10 000| = 80dB Av = log|1000| = 60dB Av = 10020log|100| = 40dB Av = 1020log|10| = 20dB Av = -1020log|-10| = 20dB Av = log|0.1| = -20dB Av negative - indicates a phase change (no change in dB) dB negative - indicates signal is attenuated

Amplifiers Example 1.1

An amplifier transfer characteristic that is linear except for output saturation. Amplifiers Saturation An amplifier transfer characteristic that is linear except for output saturation.

An amplifier transfer characteristic that shows considerable nonlinearity. (b) To obtain linear operation the amplifier is biased as shown, and the signal amplitude is kept small. Amplifiers Non-Linear Transfer Characteristics and Biasing

Circuit model of a voltage amplifier EPOLY is a dependent source is SPICE; a voltage controlled voltage source (VCVS) EPOLY has a gain of Avo The input to EPOLY is the voltage across Ri V out = A vo V in Ri = input resistance R o = output resistance + V out - + V in - I = 0 Amplifiers

Voltage amplifier with input source and load What should we design Ro to be? Av = Vout/Vin = Avo RL/(RL + Ro) Let Ro < < RL to make Av maximum Ideally Ro = 0 + V out - + V in - Avo - gain of VCVS only, o indicates output is open Av - gain of entire circuit Av changes with circuit, Avo does not! Amplifiers

Input resistance of amplifier circuit + Vout - + Vin - What should we design Rin to be? Vin = Vs Ri/(Ri + Rs) Let Rin >> Rs to make Vin = Vs Ideally Rin = infinity If Rin = infinity, then all of Vs makes it to the the amplifier; otherwise part of the signal is lost Amplifiers

Basic characteristics of ideal amplifier For maximum voltage transfer Rout = 0 Rin = infinity Amplifiers

Example 1.2

Amplifiers Example 1.2

Amplifiers Example 1.2

Circuit Models For Amplifiers Voltage Amplifiers Common Models Show example on board

Circuit Models For Amplifiers Example 1.3 Class assignment

Circuit Models For Amplifiers Other Amplifiers Current Transconductance Transresistance

Circuit Models For Amplifiers Example 1.4 Large-signal equivalent-circuit models of the npn BJT operating in the active mode.

Frequency Response of Amplifiers Bandwidth

Single-Time Constant Networks Frequency Response of Amplifiers Bandwidth RC Circuits – Class Exercise

(a) Magnitude and (b) phase response of STC networks of the low-pass type. Frequency Response of Amplifiers Bandwidth

Frequency Response of Amplifiers

Frequency Response of Amplifiers Bandwidth

(a) Magnitude and (b) phase response of STC networks of the high-pass type. Frequency Response of Amplifiers

Frequency Response of Amplifiers Example 1.5 Class assignment

Frequency Response of Amplifiers Classification of Amplifiers Based on Frequency Response

Frequency Response of Amplifiers Exercise 1.6 Class assignment

The Digital Logic Inverter Function Transfer Characteristics Noise Margins

The Digital Logic Inverter Function Transfer Characteristics Noise Margins

The Digital Logic Inverter Inverter Implementation