KMUTT: S. Srakaew

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CPE 221 Introduction

What is “Electronics”?

Electric circuit

Connections of conductive wires and passive devices

Electronics circuit

Electric circuit that contains both passive and active devices

KMUTT: S. Srakaew

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CPE 221 Introduction

Passive devices

Resistor

Voltage-current relation: V = R I, v(t) = R i(t)

Inductor

Capacitor

Voltage-current relation: v(t) = L di(t)/dt

Voltage-current relation: i(t) = C dv(t)/dt

KMUTT: S. Srakaew

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CPE 221 Introduction

Active devices

Diodes

Bipolar junction transistors (BJT)

Field-effect transistors (FET)

KMUTT: S. Srakaew

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CPE 221 Introduction

Active devices (Cont’d)

Linear integrated circuits

Operational amplifiers

Other solid-state devices

KMUTT: S. Srakaew

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CPE 221 Introduction

Basic circuit analysis

KCL

Summation of currents flow in to (or out from) a node is zero

KVL

Summation of voltages across all elements in a mesh is zero

Norton and Thevenin equivalent circuits

A two-terminal network can be represented as a current source connected in parallel with Norton’s equivalent resistance(or a voltage source connected in series with Thevenin’s equivalent resistance)

KMUTT: S. Srakaew

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CPE 221 Introduction

Example: Use KCL to find all node voltages

V1

V2

V3

1SN ,2 &3 :

- 5 V1

- 25/ V2

- 20/ V3

40 0/ = Voltage source 60V:V

1 - V

2 - 60=

Voltage source 100V:V1

- V3

100

V2

V=1

60+V3

V=1

- 100

8 V1

10+ V2

5+ V3

1000

, 81

10+ (V1

60 5+ ) + (V1

- 100 1000) =V1

V= ?,2

=?, V3

= ?

KMUTT: S. Srakaew

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CPE 221 Introduction

Example: Use KVL to find all mesh currents

i1 i

2i3

i4

KMUTT: S. Srakaew

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CPE 221 Introduction

Example: Find Thevenin’s and Norton’s equivalence of the circuit below:

KMUTT: S. Srakaew

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CPE 221 Introduction

Homework, Lab and Project policy

Homework assignments due every week( about 10)

Lab assignments due every other week (about 6)

Project assignments due every four week (about 4)

KMUTT: S. Srakaew

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CPE 221 Introduction

Homework Assignment 1

Circuit analysis (KCL, KVL)

Connections of conductive wires and passive devices

Thevenin and Norton Equivalent circuits

Electric circuit that contains both passive and active devices

KMUTT: S. Srakaew

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CPE 221 Introduction

Lab Assignment 1

Simulation of simple circuits

Select a circuit containing passive devices and use a simulation program(i.e., EWB, Protheus, etc)to simulate its behavior

KMUTT: S. Srakaew

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CPE 221 Introduction

Project topics

Class A amplifierClass B amplifierClass C amplifierClass D amplifierDimmerSwitching power supplyVoltage regulatorMotion detection

DC Motor control

Projects are not limited to the following topics. Students arefree to propose others.