Difference Between Active and Passive Component

In the present time, we see lots of electronic devices around us like TVs, fans, ACs, laptops, etc these electronic devices have electric circuits and integrated circuits inside them. Electric Circuit can be defined as a closed-loop or path of electrical components through which current can flow. An electric circuit consists of various electrical components. All electronic circuits are made up of resistors, capacitors, inductors, voltage sources, current sources, transistors, etc. These electrical components are the basic building blocks of any electronic device. This electrical component can be an Active Component or Passive Component the power delivering and absorbing nature.

An active Component is a component that delivers power to an electric circuit or components that provide energy to an electric circuit. Passive components are the components that are responsible for absorbing power or energy, components like capacitors and inductors store the energy for further use. Active and Passive components are responsible for the power or energy conservation in the circuit. Apart from this direction of the current decides the nature of the component, componentscurrent current flows outward from the component then it is an Active Component, and if the current flows towards or inwards from the component then it is a Passive Component. In this article, we will get to know about Active, Passive Component, Differences between Active and Passive Components.

Active and Passive component in circuit

What is an Active Component

Active components are electronic component that deliver or supply power or produce energy in form of voltage or current . These components depends on the external power source to control or modify electrical signals . Active components are able to control and amplify flow of current in electric circuit . These components do not store power or energy , they provide energy to electric circuit . They are also responsible to perform function like Amplification , Rectification , Switching or we can say that they influence circuit actively .

Following are some example of Active Component

Voltage Source

Voltage source is two terminal active device used to maintain fixed voltage in circuit and also provide the potential difference between two points .Ideal voltage source can be defined as voltage source having internal resistance zero and deliver constant voltage regardless of current drawn though it .When current leaves from positive terminal than power is deliver .Example of voltage source are batteries , generators etc.

Voltage Source

Current Source

Current Source is two terminal active device that provide a fixed magnitude current in a circuit . A ideal current source have infinite resistance and provide constant current independent of any load .

Current Source

Diodes

Diode are two terminal unidirectional active component that allows current to flow in one direction. If it is forward biased than it allow current to pass through if it it Reverse biased than it is open circuit and do not allow flow of current thorough it . However all diode are not active component .Diode are of many types like PN diode, LED etc . The main application of diodes are to convert AC signal to DC signal , allow one direction flow of current , used in creating power supplies and voltage doublers etc.

Diode

Transistor

Transistor are three terminal device formed by joining p and n type semiconductor one after other . BJT is transistor having three terminal Base , Emitter and Collector . When a small current is applied to Emitter and base a large current flows through Collector and emitter and hence can be used as amplifier. Some of the application of Transistors are Amplifier , used in digital logic Circuit , used in automatic switches and voltage regulators .

Transistor

What is a Passive Component

Passive components are electronic component that absorb or store the energy in circuit . These components do not depend on external power source for their operation . They are not able to control the flow of current rather it influence the current in circuit . As the name suggest “Passive” they perform operation like storing , releasing energy . They can only receive energy and can either store , absorb or release it in one or other form of energy . They can not provide gain or amplification to signal rather they decrease the energy or strength of signal without distorting it .

Following are some example of Passive Component

Resistor

Resistor is two terminal passive device that can not deliver energy but when current flows across it voltage drop takes place and energy is lost in the form of heat . It influence or regulate the current flow in circuit . If resistor is large than current flows in circuit is small and vice versa . It is linear element that follows ohm’s law V= I/R . Unit of resistor is ohm (Ω) .

Resistor

Capacitor

Capacitor is two terminal device that store energy in form of electric field between its two plates for future use. When DC source is applied than it get fully charge and after fully charging it does not allow flow of current through it or we can say that in steady state it becomes open circuit . When AC source is applied it continuously charges and discharges as the direction of current changes. It is also linear element and it is given as C= Q / V . Its unit is Farads (F)

Capacitor

Inductor

Inductor is two terminal Passive component that store electrical energy in form of magnetic field between its coil . It allows DC source to pass through it and in steady state it become short circuit . It does not allow AC and at frequency it does not support flow of current through it . DC passes through it as like it passes in conductor but large magnetic filed is generated in AC . It is also linear element and its unit is Henry (H).

Inductor

Transformer

Transformer is passive component used to transform power from one circuit to other in form of magnetic field through coils. It has two coil Primary core and Secondary coil . In Primary coil input power is supplied and in Secondary coil load is connected to which power is delivered . It work in principle of Electromagnetic Induction. It is used to step up and step down the voltage but energy and power remain constant .

Transformer

Difference Between Active Component and Passive Component

Electric circuits consist of both Active and Passive Components but both have different behavior . Following are the difference between Active and Passive Component.

ACTIVE COMPONENT	PASSIVE COMPONENT
Active component is component which only deliver power to circuit .	Passive component is component which absorb or store the energy or loss it in form of heat.
Common example of Active Components are Voltage source , current source ,diode , dc generators etc .	Common example of Passive components are Resistor ,Capacitor, Inductor , Motors etc.
It can control the flow of current in the circuit.	It cannot control flow of current in the circuit but it can influence current flow in the circuit.
They provide Power gain in circuit.	They provide Power Loss in circuit.
They need an external source for operation.	They do not require any external source.
Active Component usually have unidirectional nature.	Passive component mostly have bidirectional nature.
They can be categorized as non-linear element.	They can be categorized as linear element.
Active component act as Generator.	Passive component act as Attenuators.
They are able to do the amplification of signal that is they increase the signal strength because they have power gain more than 1.	Passive Component can not amplify the signal because they do not provide power gain and have power gain less than 1.
For Active element Slope of voltage vs current graph is negative that is ratio of voltage to current at any point is negative .	For Passive Element slope of voltage vs current is positive , ratio of voltage to current at any point is positive.
They act as power source in circuit .	They act as Load in circuit.
Active component receive energy in the form of thermal, chemical and hydraulic energy from external source and provide the energy to circuit in form of electrical energy.	They receive the energy in form of electrical energy and store it in form of either magnetic or electric field or radiate in form of heat or light .
Voltage vs current graph of Active component lies in 2nd and 4th quadrant.	Voltage vs current graph of Passive component lies in 1st and 3rd quadrant.
Active component can deliver or absorb the power depending on the direction of current through it.	Passive component cannot deliver power they can only absorb it.
They are energy donor.	They are energy absorber.

Application of Active Component

Following are the some of the applications of Active Component

• They are used in Space Technologies
• Used in Smart phones and devices
• Used in Automobiles
• They are used in all the electrical Appliances

Application of Passive Component

Passive component are used in all the application where Active Components are used apart from this there are some basic applications

• They are used in amplifier circuits.
• They are used as energy storing element in devices like power bank.
• They are used in feedback network
• They helps in biasing of electric circuits.

Conclusion

In this article we have learnt about Active and Passive components and difference between Active and Passive Component .The difference Active and Passive components is how current flows through them . Both Active and Passive component plays a vital role in electric circuit . Active Components are responsible to control the flow of current where as Passive component do not control the flow of current but it can influence the flow of current . Active components are responsible to deliver or provide energy to circuit where as Passive component handle this energy in electric circuit by storing it in form of Magnetic or Electric field or in some other terms. To find if component is Active or Passive check power across it . If power is declined than its is Passive and if power amplifies or increases it is Active Component. Both Components are widely used in all the electronic circuits .

FAQs on Difference Between Active and Passive Component

What is LED

LED stands for Light Emitting Diode . LED emits light when electric current flows through it .

What is Zener Diode

It is highly doped semiconductor diode which function in reverse direction .

What is ICs .

ICs stand for Integrated Circuits , it is small chip in which multiple electronic components are fabricated to perform complex function . It is also an active component.