Difference Between Active and Passive Components

Table of Contents

We are writing about the difference between active and passive components. A critical factor that distinguishes types of electronic components from each other is whether they are passive or active. Still, many people are unsure of exactly what that difference involves. Here we want to clarify these concepts. So, we’ll introduce active and passive elements. Then, we’ll talk about their differences.

Active Elements

Before paying attention to the difference between active and passive components, let’s introduce the active component. Active elements in the circuit are components that provide power or energy to the circuit by extracting the power from an external source as well as the ability to provide the energy remains for an unlimited period till the presence of an external source.

Since active elements afford the power to the circuit in which they are applied, they work as generators. Moreover, these components have the ability to control the flow of current within the circuit.

The elements like a transistor, diode, op-amp, etc., are identified as active components in any circuit. Let us take a look at the brief discussion of these mentioned components:

Diode

Diodes are fundamentally semiconductor materials that are comprised of p and n-type semiconductor materials. A diode is two-terminal equipment.

A diode is an active component utilized to direct the current flowing within the circuit by just allowing conduction in one direction.

Difference between active and passive components — The symbol of a diode (reference: vivadifferences.com)

Transistor

A transistor is a 3 terminal equipment that displays amplifying action. As we have explained, active components use the power from an external source and supply it to the circuit they are connected to.

Likewise, a transistor performs amplifying the effect of the current in a circuit.

Transistors are basically classified as BJT and FET.

All You Should Know About Active Components

Now, we want to introduce important tips about active components to understand the difference between active and passive components better.

The active component is a piece of equipment that can amplify the output signal of an electronic circuit in the amount more than in the input signal.
Active components demand an external power source to provide energy to the circuit.
These components are unidirectional
They operate as a heat source and hence are capable of providing the power increase.
Active components produce or deliver power or energy in the form of current or voltage.
When active components present in any circuit, they show some level of control on the current flowing within the circuit.
Active components act as generators because of their power providing ability.
Active components cannot store energy.
Active components are classified in the non-linear category.
Active components deliver energy or power to the circuit.
Active components are extensively applied in personal computers (PC).
They can amplify the signal due to giving gain, more than one.

Passive Elements

In an effort to distinguish between active and passive components, let’s now introduce the passive component. Passive elements in a circuit are components that cannot produce energy in the circuit in which they are operated. However, they can store or consume the power present in the circuit.

Furthermore, passive elements do not require external electrical power for their performance. In addition, passive components can be connected in both directions in the circuit because of their bidirectional nature. Due to their power storing and consuming capacity, they perform as attenuators. Passive components are inductor, resistor, and capacitor, etc. Let us take a look at a short description of these components.

Resistor

Resistors are the passive elements that hold the ability to restrict the current flowing within the circuit when they are applied in any circuit.

The quantity that weighs the amount of restriction given by resistors is called resistance. Resistance has the unit of ohm.

The resistance of a particular resistor is calculated by:

R=\frac { V }{ I }[\katex]

where

"V" is the voltage drop across the resistor and

"I" indicate the current flowing through that specific resistor.

Capacitor

A capacitor is a device that stores the electric charges flowing over it in the two capacitive plates.

The amount of charge collected by the capacitor is defined as capacitance, which has the unit of farad.

The capacitance in a capacitor is given by:

C=\frac { Q }{ V }[\katex]

where

"Q" describes the charge collected and

"V" expresses the voltage across the plates of the particular capacitor.

Inductor

Inductors are elements that can store energy. However, inductors store power in the form of a magnetic field, unlike capacitors.

So long as the current flows through the circuit, energy is stored in the turns of the coil. Inductance is the unit utilized for estimating the magnetic field stored in the coil, and its unit is Henry.

Inductance is calculated by:

L=\frac { \phi }{ I }[\katex]

where

"?" is the flux linking

and

"I" denotes the current flowing within the inductor.

All You Should Know About Passive Components

Here, we want to introduce essential points about passive components to understand the difference between active and passive components better.

Passive components are tools that control or alter the output of an electronic circuit without playing an active function in their performance.
Passive components do not require an external power source since they cannot supply power and can just store or transfer the power available in the circuit.
These components are bidirectional in nature.
Passive components serve as a heat sink and hence cannot afford the power gain.
Passive components use or collect energy in the form of current or voltage.
Passive components are truly not intended to control the current flowing within the circuit.
Passive components operate as attenuators because of their absorbing tendency.
Passive components can collect and store the energy (in the case of capacitor and inductor).
The passive components are classified in the linear category.
The passive elements use the energy or power in the circuit.
Passive components are widely employed in MP3 players, washing machines, etc.
These components are not capable of amplifying the signal due to having a gain of less than one.

Key Difference Between Active and Passive Components

Now, to illuminate the difference between active and passive components, twelve differences between active and passive components are presented in the table below.

BASIS OF COMPARISON	ACTIVE COMPONENTS	PASSIVE COMPONENTS
Description	Active component is equipment that can amplify the output signal of an electronic circuit in the amount more than in the input signal	Passive components are tools that control or alter the output of an electronic circuit without playing an active function in their performance
External Power Source	Active components demand an external power source to provide energy to the circuit	Passive components do not require an external power source since they cannot supply power and can just store or transfer the power available in the circuit
Nature	These components are unidirectional	These components are bidirectional in nature
Functionality	They operate as a heat source and hence are capable of providing the power increase	Passive components serve as a heat sink and hence cannot afford the power gain
Power	Active components produce or deliver power or energy in the form of current or voltage	Passive components use or collect energy in the form of current or voltage
Current Flow Control	When active components present in any circuit, they show some level of control on the current flowing within the circuit	Passive components are truly not intended to control the current flowing within the circuit
Function	Active components act as generators because of their power providing ability	Passive components operate as attenuators because of their absorbing tendency
Energy Storage	Active components cannot store energy	Passive components can collect and store the energy
Category	Active components are classified in the nonlinear category	The passive components are classified in the linear category
Circuit	Active components deliver energy or power to the circuit	The passive elements use the energy or power in the circuit
Application	Active components are extensively applied in personal computers (PC)	Passive components are widely employed in MP3 players, washing machines, etc.
Signal Amplification	They can amplify the signal due to giving gain, more than one.	These components are not capable of amplifying the signal due to having a gain of less than one.