Basic Components-Passive

Circuit Components

• Passive components
• Active  components

The main difference between active and passive components is that active ones require to be powered in some way to make them work but passive doesn't need external power.

      Passive Components : Resistor, capacitor, Inductor etc

      Active Components : Diode, Transistor, ICs etc

Now we can familiarize the basic passive components.

Resistor
Gives resistance to the flow of current.Fixed & Variable type.

The colour coding of resistors is shown below. 

   





Fixed Resistance: the resistance value is fixed. They can be wirewound type, metal film types, thick or thin film type, foil type etc.

Variable resistors: Can vary the resistance values. Some examples are shown below.

Resistance networks (Packs): it is a network of resistors as shown below. 

Connections of resistors

Resistors in series

The Current through all the resistors in series is same but the voltage drop will be different. The equivalent    resistance is the sum of all the resistances 

   

 R_eq = R1 + R2

Resistors in parallel

       The voltage between resistors in parallel is same but the current may be different. 

   

      
Capacitor

      Used to store energy. capacitor stores charge. Unit of capacitance is Farad. Blocks Direct Current  & allow to  pass Analog Current. Fixed and variable capacitors are there. 

Fixed type

  Variable capacitors

 Connection of capacitors      

 Capacitors in Series

Equivalent capacitance is given by 

    

Capacitors in parallel

The equivalent capacitance is given by

Inductors

       It stores energy as magnetic field. Simply it is a coil of wire. Inductance is typified by the behavior of a coil of wire in resisting any change of electric current through the coil. Unit of inductance is Henry. If inductance is represented as L, then the   

      

 emf generated in the coil is given by 

 emf, e= -L(dI/dt)

There are different types of inductors based on their type of core and inductor can be fixed as well as variable.

Connection of Inductors

 Inductors in series 

    

Inductor in parallel

       We can discuss the other components like diode transistor etc in the following pages.

        

    Please Note: 

       Most of the pictures i used in this blog are from other sites. If anyone finds any errors or flaws in the contents of the page, please correct me.

A Brief Explanation of the Fundamentals

Electronics deals with the dynamics of electrons. Let us go through some fundamentals of electronics.

Charge

No one knows what really is charge, any more than, it is a physical property of matter that exhibits electrostatic   attraction or repulsion in the presence of other charge. It is a conserved quantity; charge cannot be created nor be destroyed. The unit of charge is  Coulomb. Like charges repels and unlike charges attracts.

Charge of one electron =1.6x10^{^ -19}

Voltage

Voltage is the electric potential energy per unit charge, measured in joules per coulomb (Volts). Simply it is the potential difference between two points.

Current

It is the rate of charge flow through a conductive medium. unit is Ampere.

I=dQ/dt

Resistance

It is the opposition to the current flow through a conductor. It is the inverse of conductance. Unit is Ohm. 

where, 

R is the resistance

 is the length of the conductor

A is the cross sectional area of the conductor

p is the resistivity of the conductor

Frequency

Frequency is a parameter describing the property of a signal. Frequency is defined as the number of cycles per second. It is the inverse of time period of the signal. Unit is Hertz (Hz).

Alternate current (AC)

The direction of current flowing in a circuit is constantly being reversed back and forth. Our (Indian) Domestic electric supply is AC current.

Direct Current (DC)

The electrical current is flowing in only one direction in a circuit. The frequency of DC is zero. Batteries are examples of DC source.

Conductors/Semiconductors/Insulators

An electric conductor is a material that conducts electricity. it's band gap is very small.

Insulators will not allow the flow of electric current through it. The band gap is very large.

Semiconductors acts as insulators at absolute zero but its conductivity increases with increase in temperature. band gap is greater than that of conductors but much less that insulators. Intrinsic semiconductors are pure form semiconductors while extrinsic semiconductors are formed by doping impurities to intrinsic semiconductor for improving the conductivity. Extrinsic semiconductors are of two types; P-type  whose majority carriers are holes and N-type whose majority carriers are free electrons.

The band gaps of the above three types of materials are shown below.

     `

     Please Note: 

       Most of the pictures i used in this blog are from other sites. If anyone finds any errors or flaws in the contents of the page, please correct me.

Introduction

Greetings to all!!!

Welcome to easyelectronics

For some months, i was thinking of starting blogging. But what to write? Now i am working on embedded systems and hence i thought why can't i start a blog dealing with electronics and embedded system? And then comes this blog...

It's the world of electronics. It would be difficult to find some system without some electronic part. I am very much happy to start this blog since i can share some of my ideas and knowledge through this.i am trying to give some idea on the basics of electronic components, circuits designs, microcontroller, easy programming of microcontrollers etc.

Most of the contents of this blog may be available in many other sites. But the speciality of this blog is that, the things will be written and arranged so that the reader can understand the practical applications and do some hands-on assignments. The blog also contains some circuits that can explain the property of  components, some interesting applications etc. My intended crowd is, students who are trying to explore more in electronics and embedded systems.

I am expecting support from everyone since i am new to blogging.  And kindly correct me if you find any mistakes.

yours sincerely,
Thomas