One of the biggest questions that we get asked by beginners to electronics is “What is the difference between passive and active components?” In this blog, we’re going to be discussing the differences between the two with examples.
Active components rely on a form of external energy to work and usually have the ability to amplify or inject more power into a circuit, here’s a couple of active component examples.
- Diodes - They are great little components that are used to help direct the flow of current within a circuit, making them really good at helping prevent damage to other components that might be damaged if energy flowed the wrong way.
- Transistor - This tiny component can be used to amplify a current, taking a small current of energy and outputting a larger current.
While on the other hand, passive components do not require sources of energy to function, they are mainly used store or dissipate the energy within a circuit. Let's have a brief look at three of the most common passive components:
- Capacitor - These components store energy as an electrostatic charge. A capacitor is made up of two or more conductive plates each being separated by a dielectric sheet, they will also stop and block any flows of direct current (DC) but have little to no impact on alternating current(AC).
- Inductor - Like capacitors, these are used for storing energy or delivering a charge, however, unlike a capacitor, this is stored as an electromagnetic charge. Within a circuit, an inductor will have a high impedance on alternating current (AC) while having very little impedance on direct current (DC).
- Resistors - As the name suggests these resist the flow of electrical currents within a circuit. They help to lower the energy through the system as they will consume energy and help dissipate it rather than storing it as a charge, resistors will impede both alternating currents(AC) and direct currents(DC).
So to summerise, an active component requires an external power supply in order to work, whereas passive components do not. There we have it, we hope that helped clear things up with the differences between Active and Passive components.