Microelectronic Circuits Microelectronic Circuits Ch. 1 Introduction INHA Univ. 1 전자회로 1 Chapter 1: Introduction to Electronics 인하대학교 정보통신공학부 2008 년

Microelectronic Circuits Microelectronic Circuits Ch. 1 Introduction

INHA Univ.INHA Univ.

1

전자회로 전자회로 11Chapter 1: Chapter 1: Introduction to Introduction to ElectronicsElectronics

인하대학교정보통신공학부

2008 년 2학기



2

Course AdministrationCourse Administration Professor: 정 덕진

Office: Hi-Tech 빌딩 510 호 TEL: (032) 860-7435 Email: [email protected] http://vlsi.inha.ac.kr/

Class Web Site: Cyber-class in Inha Univ.



3

Text and Reference booksText and Reference books

Text: Microelectronics Circuits (5th Edition), Sedra/Smith Class notes on the web site

– Cyber-class in Inha Univ.

Reference:



4

Course ContentsCourse ContentsPart I. Devices and Basic Circuits

Ch.1. Introduction to Electronics • Definition about signal / Analog-digital / Continuous-Discrete 등

Ch 2. Operational Amplifiers (OP-AMP)• Ideal OP-AMP • Practical OP-AMP 및 연결방법

Ch. 3. Diodes • Ideal Diode • Practical Diode condition 및 회로 / 특수 Diode / Zener Diode

Ch. 4. MOS Field-Effect Transistors (MOSFETs)• 물리적인 특성 , MOSFET circuits, amplifiers

Ch. 5. Bipolar Junction Transistors (BJTs)• 물리적인 특성 , npn/ pnp Tr., BJT circuits, • small-signal operation and models, • BJT amplifiers



5

Course ContentsCourse ContentsPart II, Analog and Digital Integrated Circuits

Ch. 6. Single-Stage Integrated-Circuit amplifiers

Ch. 7. Differential and Multistage Amplifiers

Ch. 8. Feedback

Ch. 9. Operational-Amplifier and Data-Converter Circuits

Ch. 10. Digital CMOS Logic Circuits



6

Grading InformationGrading Information Grade determinants

Quiz/Homeworks ~ 10%– Will be scheduled later.

Exam-2 ~ 25%– Will be scheduled later

Final Exam ~ 25%– Will be scheduled later

Projects ~ 30%– Due at the beginning of class on the due date (No extensions).

출석 ~ 10%



7

Chapter 1 Chapter 1 Introduction to ElectronicsIntroduction to Electronics



8

Introduction Introduction Microelectronics: 작은 실리콘 ( 실리콘 칩 ) 에 수백만개의 회로를

만들수 있는 능력을 가진 Integrated Circuit (IC) technology 를 말한다 . Microelectronics circuit example: Microprocessor

– Intel Pentium, AMD Athlon, DRAM, CDMA modem chip, ASIC, FPGA etc.

Chapter 1 에서 배울점 . Basic concept 와 terminology 를 이해하며 , 주로

단일소자를 이용한 signal amplification ( 증폭 ) 에 중점을 둔다 .

Linear amplifier 에 대한 모델들을 이해하고 , 그 모델을 이용해서 실질적인 amplifier circuits ( 증폭회로 ) 들을 설계하고 분석한다 .



9

The Transistor RevolutionThe Transistor Revolution

First transistorBell Labs, 1948



10

The First Integrated Circuits The First Integrated Circuits

Bipolar logic1960’s

ECL 3-input GateMotorola 1966



11

Intel 4004 Micro-ProcessorIntel 4004 Micro-Processor

• First microprocessor designed In 1971• 1000 transistors• 1 MHz operation



12

Intel Pentium (IV) MicroprocessorIntel Pentium (IV) Microprocessor

• Released in 2000

• 42 million transistors

• 0.18 micron tech.

• > 1GHz



13

Silicon WaferSilicon Wafer

Single die

Wafer



14

Transistor CountsTransistor Counts

1,000,000

100,000

10,000

1,000

10

100

11975 1980 1985 1990 1995 2000 2005 2010

8086

80286i386

i486Pentium®

Pentium® Pro

K1 1 Billion Billion

TransistorsTransistors

Source: IntelSource: Intel

ProjectedProjected

Pentium® IIPentium® III

Courtesy, Intel



15

Design Abstraction LevelsDesign Abstraction Levels

n+n+S

GD

+

DEVICE

CIRCUIT

GATE

MODULE

SYSTEM



16

Signals Signals

Signals: 정보를 포함한 신호 signal processing : 정보를 추출 , 가공 , 전송하는 과정

– Acoustic signal – Electrical signal – Optical signal

여기서는 주로 Electrical signal 을 취급한다 .



17

1.1 Signals 1.1 Signals

In Fig.1.1(a), Signal is represented by a voltage Vs(t) having a source resistance Rs.

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

0sR sR



18

Figure 1.2 An arbitrary voltage signal vs(t).

Vs(t) = Rs is(t)



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1.2 Frequency Spectrum of Signals1.2 Frequency Spectrum of Signals

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

1) Signal 의 표시방법

1)-1. Time Domain

Va(t) = Va sin t

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



20

1)-2. Frequency domain1)-2. Frequency domain

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

• Fourier series 와 Fourier transform에 의하여 frequency spectrum 이라는 신호표현이 얻어진다 .• 모든 signal 은 Fourier transform 에 의해서 주파수 영역으로 구분 가능



21

2)-2. Frequency domain2)-2. Frequency domain

1

0 2sin2cos2 n

nn T

tnb

T

tna

a

Tn dt

T

nttf

Ta 0

2cos)(

2예 )

즉 . Fig. 1-4 의 파형은 ( )

: fundamental frequency : 3rd harmonic frequency

: 5th harmonic frequency

실효치 (Root-Mean-Square, rms) 로써 표시되기도 하며 sine wave 시 peak

치의 이다 audio band : 20 ㎐ ~ 20 ㎑ (20 ㎑ 이상은 사람의 귀에서 인식 불가능 )

Tw

20

)5sin5

13sin

3

1(sin

4)( twtwtw

vtv ooo

twosin two3sin3

1

two5sin5

1

2

1

Tn dt

T

nttf

Tb 0

2sin)(

2



22

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

Unlike the case of periodic signals, where the spectrum consists of discrete frequencies (at 0 and its harmonics), the spectrum of nonperiodic signal contains in general all possible frequencies, that is continuous function of frequencies.



23

1.3 1.3 Analog and Digital SignalsAnalog and Digital Signals 특성에 의한 분류

Analog signal : Fig. 1.2 Digital signal :

형태에 의한 분류 Continuous-time signal : Discrete-time signal :

Digital signal 의 장점 noise 에 의한 문제를 쉽게 치유가능 저전력으로 전송가능



24

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

Sampling: At each intervals along the time axis we have marked the time instants t0, t1, t2, and so on. At each of these time instants the magnitude of the signal is measured.

Continuous-time signal Discrete-time signal

Analog Signal



25From http://www.amd.com

Digital SignalDigital Signal After quantized, discretized, or digitized, the resulting digital signal is a

sequence of numbers that represent the magnitude of the successive signal samples.

Binary number system results in the simplest possible digital signals and circuits.

In binary system, each digit in the number takes on one of only two possible values, denoted 0 and 1.

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



26

Analog-to-Digital (A/D) ConverterAnalog-to-Digital (A/D) Converter

A/D converter accepts at its input the samples of an analog signal and provides for each input sample the corresponding N-bit digital representation at its N output terminals.



27

1.4 Amplifiers1.4 Amplifiers Signal Amplification

Signal 을 증폭할 때 선형성이 유지되어야 하며 , 선형성이 유지되지 않으면 Nonlinear Distortion 이 발생 .

A : Amplifier gain, 만약 A=const. 이면 linear Amplifier 라고 부른다 .

Voltage gain (Av) ≡ , current gain (Ai) ≡ , power gain (Ap) ≡

∴ Ap = Av Ai

i

o

v

v

i

o

i

i

ii

oo

i

L

iv

iv

P

P

)()( tAvtv io

Transfer characteristic of a linear amplifier



28

Expressing Gain in Decibels Voltage gain in decibels = 20 log |Av| dB Current gain in decibels = 20 log |Ai| dB Power gain in decibels = 10 log |Ap| dB

A negative gain Av means that there is a 180º phase difference between input and output signals.

Amplifier Power Supplies

|100 0

2211

iPdc

L

dissipatedLidc

dc

P

P

PPPP

IVIVP

V+ = 10V, V- = -10VVo = Vpeak, RL=1K

DC power

: amplifier efficiency



29

Example 1.1

V+ = 10V, V- = -10V Vo = Vpeak, RL=1K,

mAII 5.921 mAIi 1.0 peaki VV 1

i

ov V

vA 9log20 10vA

k

V

R

vI peak

L

oo 1

990

1.0

9

i

oi

I

IA dBAi 1.3990log20

mWIVP ormsormsL 5.402

9

2

9 mWIVP irmsirmsI 05.0

2

1.0

2

1

WWP

PA

I

LP /810

05.0

5.40 dBAP 1.2980log10

%3.21100

1495.4005.0190

1905.9105.910

dc

L

LIdcdissipated

dc

P

P

mWPPPP

mWP

91

9

peak

peak

V

VdB1.19

peakmA9



30

Amplifier Saturation

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

The output voltage cannot exceed a specified positive limit and cannot decrease below a specified negative limit. L+ : Positive saturation level L-: Negative saturation level

Note that the peaks of the larger waveform have been clipped off because of amplifier saturation.



31

Nonlinear Transfer Characteristic and BiasingNonlinear Transfer Characteristic and Biasing

• In practical amplifiers the transfer characteristic may exhibit nonlinearities of various magnitude.

• The transfer characteristic is nonlinear and, because of the single-supply operation, is not centered around origin.

• Biasing: signal 의 전부분이 증폭될 수 있도록 DC voltage 를 부가하여 중심점을 옮기는 것 .

• See page.19.

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, VDD.



32

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).

Example 1.2 Find the limits L- and L+ and the corresponding Find the VI that results in VO = 5V and the voltage gain at the corresponding

operating point

1) L- = 0.3V, = 0.3V in Eq. (1.10)

= 0.690V

2) L+ =

3) VI = 0.673V by substituting = 5V

in Eq. (1.10)

4) Av = -200 V/V by evaluating the

derivative at = 0.673V

)3.00(1010 4011

0VvandVvforev

OI

vI

Iv

Ov

Iv

V101010 11

Ov

IOdvdv /

Iv



33

Symbol ConventionSymbol Convention IA: Direct-current (dc) current VC: Direct-current (dc) Voltage iA(t): Instantaneous current (Total current) iC(t): Incremental current signal VDD: Power-supply (dc) voltage IDD: dc current drawn from the power supply



34

Circuit Models for AmplifiersCircuit Models for Amplifiers Circuit Model 의 4 가지 유형

Vi R i

R o

AvoViR i R oA isii

ii

R i R oG mVi

io

ViR i R m ii

ii

Vo

R o

Voltage Amplifier (Avo : unitless) Current Amplifier (Ai : unitless)

Transconductance Amplifier (Gm : conductance)

Resistance Amplifier (Rm : Resistance)



35

1.5.1 Voltage Amplifiers1.5.1 Voltage Amplifiers

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



36

Vi R i

R o

AvoVi R i R oA isii

ii

R i R oG mVi

io

ViR i R m ii

ii

Vo

R o

Voltage Amplifier (Avo : unitless) Current Amplifier (Ai : unitless)

Transconductance Amplifier (Gm : conductance)

Resistance Amplifier (Rm : Resistance)

The Four Amplifier TypesThe Four Amplifier Types



37

Frequency Response of AmplifiersFrequency Response of Amplifiers Amplifier frequency response: 다른 주파수들을 가지고 있는 Input

sinusoids 에 대한 응답에 관한 특성 . Measuring the Amplifier Frequency Response

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

Fig. 1.20 depicts a linear amplifier fed at its input with a sine-wave signal of amplitude Vi and frequency

Whenever a sine-wave signal is applied to a linear circuit, the resulting output is sinusoidal with the same frequency as the input.

Linear Amplifier 에서는 gain 이 일정하나 일반적인 Amplifier 에서는 frequency 에 따라 증폭율이 달라진다 .



38

Measuring the Amplifier Frequency ResponseMeasuring the Amplifier Frequency Response

Figure 1.20 Measuring the frequency response of a linear amplifier. At the test frequency , the amplifier gain is characterized by its magnitude (Vo/Vi) and phase .

Magnitude of the amplifier gain (or transmission), or transfer function |T()| = Vo/Vi

Phase of the amplifier transmission: T() = Amplifier 의 Frequency response 는 amplitude response 와 phase response

를 구성한다 Amplitude response: gain magnitude |T()| versus frequency Phase response: phase angle T() versus frequency



39

1.6.2 Amplifier Bandwidth1.6.2 Amplifier Bandwidth

Express the magnitude of transmission in decibels The gain is almost constant over a wide frequency range, roughly

between 1 and 2. Amplifier bandwidth: The band of frequencies over which the gain of

the amplifier is almost constant.

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



40

1.6.3 Evaluating the Frequency Response of 1.6.3 Evaluating the Frequency Response of AmplifiersAmplifiers

In frequency-domain analysis

Vi

Vo

C c

C E

C bc

C be

C S

the Amplifier transfer function T (w) = Vo()/Vi()



41

1.6.4 Single-Time-Constant Networks1.6.4 Single-Time-Constant Networks Two examples of STC networks are

Low-pass network High-pass network

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



42

Low-pass networkLow-pass network

Vi Vo

R

C

jw 대신에 complex frequency variable s

1

11

1

)(

jwCR

jwCR

jwCV

VwT

i

o

1

1

oww

j

12

2

|

1

1log20

oww

ww

oo w

w

w

w|tan 1

)(

)()(

sV

sVsT

i

o

dB32

1log20

The transmission of low-pass network will decrease with frequency and approach zero as approach .

Low-pass filter passes low-frequency sine-wave inputs with little or no attenuation (at =0, the transmission is unity)

RCw

10



43

Bode plots of Low-pass networkBode plots of Low-pass network

Magnitude response

Phase response

3-dB frequency (0)

= corner frequency

= break frequency



44

High-pass networkHigh-pass network

Its transmission is unity at = and decrease as is reduced.

Vi VoR

C

예 ) C = 1 ㎋ , R = 1 ㏀ sol)

Transfer function :

RCjw

jw

jwCR

R

V

VwT

i

o

11)(

)/(1

1

wwj o

RCw

10

KHzw

frequencydBf

RCw

oo

o

1592

3

1010

1

1010

11 6693

610)(

s

ssT )

10(tan

)/10(1

1 61

26 ww

w

w

wwo

o

1

2tan

)/(1

1



45

Bode plots of High-pass networkBode plots of High-pass network

Magnitude response

Phase response



46

Example 1.5Example 1.5

a) Amplifier voltage gain V0 / VS , dc gain and the 3-dB frequency ?

b) RS = 20kΩ, Ri = 100kΩ, Ci = 60pF, = 144V/VkΩ , Ro = 200Ω , RL = 1kΩ, Calculate dc gain, 3-dB frequency, unit gain frequency ?

c) V0 = ?

i) Vi = 0.1 sin102t V ii) Vi = 0.1 sin105t V iii) Vi = 0.1 sin106t V iv) Vi = 0.1 sin108t V



47

Example 1.5: Solution (see pp. 36)Example 1.5: Solution (see pp. 36)a

)

Time constant

s

i

oL

Lio

sii

ss

i

ii

s

sis

ssi

isi

V

V

RR

RVV

RsCRRV

V

sCR

RV

YRV

RZ

ZVV

)1(

1

)1

(1

1

1

1

oioi w

RRC1

)||(

oL

o

o

ss

o

ww

jRR

RRV

V

1

1

1

1

1

1

isi

i

s RRsCRR ||1

1

1

1

isi

L

o

i

s RRsCRR

RR ||1

1

1

1

1

1

oww

j

K

1



48

Example 1.5: Solution (see pp. 36)Example 1.5: Solution (see pp. 36)

b) dc gain

VVK /100

1000200

1

1

10020

1

1144

3 dB frequency

kHzf

srKKpF

wo

2.1592

10

/10)100||20(60

1

6

0

6

unit gain frequency =

sr /108



49

Example 1.5: Solution (see pp. 36)Example 1.5: Solution (see pp. 36)c

) 610/1

100)()(

jwjw

v

vjwT

s

o

010

10tantan) 6

211

ow

wi

)(tvo

7.510

10tantan) 6

511

ow

wii

)(

95.91

1002

610

510

tv

gain

o

4510

10tantan) 6

611

ow

wiii

)(

7.701

1002

610

610

tv

gain

o

4.8910

10tantan) 6

811

ow

wiv

)(

4.891

1002

610

810

tv

gain

o

Gain =

t2sin10 Vt )7.510sin(95.9 5

Vt )4510sin(7.70 6 Vt )4.8910sin(1.0 8



50

1.6.5 Classification of Amplifier Based on 1.6.5 Classification of Amplifier Based on Frequency ResponseFrequency Response

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



51

1.7 Digital Logic Inverters1.7 Digital Logic Inverters1.7.1 Function of the Inverter1.7.1 Function of the Inverter

Figure 1.28 A logic inverter operating from a dc supply VDD.

A logical variable is associated with a nominal voltage level for each logic state 1 VOH and 0 VOL



52

1.7.2 The Voltage Transfer Characteristic (VTC) 1.7.2 The Voltage Transfer Characteristic (VTC)

The regions of acceptable high and low voltages are delimited by VIH and VIL that represent the points where the gain of VTC curve = -1.

VIL ~ VIH: transition region

VIL VIH Vin

Slope = -1

Slope = -1

VOL

VOH

Vout

“ 0” VOL

VIL

VIH

VOH

UndefinedRegion

“ 1”



53

1.7.3 Noise Margins 1.7.3 Noise Margins

Noise margin high

Noise margin low

VIH

VIL

UndefinedRegion

"1"

"0"

VOH

VOL

NMH

NML

Gate OutputStage M

Gate InputStage M+1

For a gate to be robust and insensitive to noise disturbance, “0” and “1” intervals (noise margins) should be as large as possible.

* Noise Margin High NMH = VOH - VIH * Noise Margin Low

NML = VIL - VOL



54

1.7.4 Ideal VTC1.7.4 Ideal VTC

Ri = Ro = 0Fanout = NMH = NML = VDD/2

g =

The ideal gate should have infinite gain in the transition region a gate threshold located in the middle of the logic swing high and low noise margins equal to half the swing input and output impedances of infinity and zero, respectively.

Ideal voltage-transfer characteristic of anIdeal inverter



55

1.7.5 Inverter Implementation1.7.5 Inverter Implementation

CMOS Inverter CMOS Inverter

Polysilicon

In Out

VDD

GND

PMOS 2

Metal 1

NMOS

OutIn

VDD

PMOS

NMOS

Contacts

N Well

Its Layout



56

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

OutIn

VDD

PMOS

NMOS



57

OutIn

VDD

PMOS

NMOS

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.



58

1.7.6 Power Dissipation1.7.6 Power Dissipation

Power dissipation: how much energy is consumed per operation and how much heat the circuit dissipates

Two important power consumption: Dynamic and static power dissipation P (watts) = CLVdd²f01+ tscVddIpeakf01+VddIleakage

f01 = P01 fclock

Dynamic power dissipation = CLVdd²f01

Static power dissipation = tscVddIpeakf01+VddIleakage

– CL: load capacitance Capacitance between the output node and ground

– Vdd: power-supply voltage



59

1.7.7 Propagation Delay1.7.7 Propagation Delay Propagation delay: time delay between switching of v1

(from low to high or vice versa) and the corresponding change appearing at the output. Propagation arises for two reasons:

– The transistors that implement the switches exhibit finite (nonzero) switching times

– The capacitance that is inevitably present between the inverter output node and ground needs to charge (or discharge) before the output reaches its required level of VOH or VOL



60

Important model – matches delay of inverter

Modeling Propagation DelayModeling Propagation Delay

vout

vin C

R

Model circuit as first-order RC network

where RC (time constant)

Time to reach 50% point is

tp = ln (2) = 0.69

Time to reach 90% point is

tp = ln (9) = 2.2



61

Figure 1.34 Example 1.6: (a) The inverter circuit after the switch opens (i.e., for t 0). (b) Waveforms of vI and vO. Observe that the switch is assumed to operate instantaneously. vO rises exponentially, starting at VOL and heading toward VOH .

Example 1.6



62

Solution)

on

on

offsetDD

offsetOLR

RR

VVVV

V55.01.01.1

1.051.0

/)55.05(5)( t

Oetv

)(2

1)(

OLOHPLHOVVtv

)55.05(2

1

ns

RC

tPLH

9.6

101069.0

69.0

69.0

113

ii) by substituting in Eq. (1.33)

i) iii)

iv) The result is

Documents

Microelectronic Circuits Microelectronic Circuits Ch. 1 Introduction INHA Univ. 1 전자회로 1 Chapter 1: Introduction to Electronics 인하대학교 정보통신공학부 2008 년