Introduction to Passive Components: Resistors, Capacitors, Inductors
Introduction to Passive Components
Resistors
- Resistors are components that are used to control the flow of electric current in electronic circuits.
- They have a fixed resistance value measured in ohms (Ω).
- Resistors follow Ohm's law, which states that the current through a resistor is directly proportional to the voltage across it and inversely proportional to the resistance.
- Resistors are used in a variety of applications such as limiting current, dividing voltages, and in pulse shaping.
Capacitors
- Capacitors store electrical energy in an electric field.
- They consist of two conducting plates separated by an insulating material known as the dielectric.
- Capacitance is the measure of a capacitor's ability to store energy, and it is measured in farads (F).
- When voltage is applied to a capacitor, charge accumulates on one plate and is repelled from the other, creating a potential difference.
- Capacitors are used in filters, oscillators, and for smoothing in power supplies.
Inductors
- Inductors store energy in a magnetic field created by the flow of electric current through it.
- An inductor is typically a coil of wire and can be categorised based on whether the wire is wound around a magnetic core or not.
- Inductance is the property of an inductor that determines the amount of energy it can store. It's measured in henries (H).
- Inductors are used in electronic filters, oscillators, and in power electronic applications.
- An important property of an inductor is that it resists changes to the current flowing through it. This is why you will often find inductors in circuits where current stabilisation is needed.