Basic elements used in electronic circuits

Unit - III

Chapter 3

ANALOG ELECTRONICS

Resistor, Inductor and Capacitor in Electronic Circuits- Semiconductor Materials: Silicon &Germanium PN Junction Diodes, Zener Diode -Characteristics Applications - Bipolar Junction Transistor-Biasing, JFET, SCR, MOSFET,IGBT - Types, I-V Characteristics and Applications, Rectifier and Inverters

RESISTORS, CAPACITORS AND INDUCTORS

Three basic elements used in electronic circuits are the resistor, capacitor, and inductor.

Resistors

A resistors represent a amount of resistance in the circuit. Resistance is a measure the flow of electric current is opposed or resisted. It is defined by ohm's law. Resistance = voltage/current

R = V /I

Resistance is measured in ohms (Ω). The symbol of resistor is shown in fig.

Two resistance are connected series as shown in fig. the equivalent resistance is R = R₁ + R₂

Two resistance are connected in parallel as shown in fig then equivalent resistance is

R = R₁ R₂/ R₁+R₂

capacitors

A capacitor represents the amount of capacitance in a circuit. The capacitance is the ability of a component to store an electrical charge.

The capacitance is defined by the equation

c = q/v

where

1 = is the charge in colombs.

v = is the voltage

In the DC circuit, a capacitor becomes an open circuit blocking any DC current from passing the capacitor. AC current only pass through a capacitor. Capacitor is measured in farads. The symbol of capacitor is two parallel lines as shown in fig.

Inductors

An inductors represents the amount of inductance in a circuit. The inductance is the ability of a component to generate EMF due to a change in the flow of current. In DC circuit, an inductor looks like a wire. It has no affect when the current is constant. Inductance has an effect when the current is change in an AC circuit. Inductance is measured in Henrys. The symbol of inductance is shown in fig. The letter L is used in equation.