Welcome to our series on how gadgets work on a component level. Electronics touch every part of our lives and make life easier and more enjoyable for us. But there’s so much we don’t know about them! If you have a smartphone or a laptop, you use an electronic device regularly. Have you ever wondered what is going on behind the scenes in your devices?
If you have, you’re in luck. We have a “How Gadgets Work” series and we’re on part three.
To recap, we’ve explained what a circuit is, printed circuit boards, and the most important circuit, the integrated circuit. We’ve discussed capacitors, which can quickly charge and discharge energy. We covered resistors, which control the voltage and current in your circuit. We’ve gone over diodes, which turn alternating currents into direct currents, protecting equipment. Finally, we looked at transistors, that are often used as switches and are integral to computers.
Now we conclude our discussion with two final components you’ll see in a circuit: inductors, transformers, relays, and quartz crystal.
An inductor is a circuit component with two terminals
- it stores energy in its magnetic field, returning it to the circuit whenever it is needed. If two inductors are placed side by side without touching, the magnetic field created by the first inductor affects the second one.
- Inductors are just made of copper wire. Their inductance is directly proportional to the number of turns in the coil.
- When current flows through a wire, it creates a magnetic field. The shape of the inductor allows a much stronger magnetic field to be created. This field, then, resists alternating current but allows direct current to flow right through it.
- Inductors are typically replaced by resistors in integrated circuits due to their bulk.
- Transformers are one of the fundamental parts of a power transmission system.
- Transformers are created by combining the inductors of a shared magnetic field. They are used to increase or decrease voltages.
- An inductor can also store energy, but only for a limited time. The energy is stored in a magnetic field, so it collapses as soon as the power supply is removed.
- This is an electromagnetic switch that can open and close circuits electronically. These are typically used to regulate low currents in a control circuit. Think of a relay as a lever. You can switch it on with a small current to turn on another circuit using a large current.
- Relays are either Normally Closed or Normally Opened. With an NC relay, the contacts stay closed when there is no power supply. In a NO relay, the contacts will either open or close shut.
- Relays can control a high current circuit by a low current signal, so most control processes use relays as the primary switching and protection devices. They can also find faults and irregularities coming in the power distribution systems.
Quartz crystals have several uses in the electronics industry, but they are mostly used as resonators in electronic circuits.
- Quartz crystals can either be manufactured or occur naturally.
- They are used to make oscillators that create an electrical signal with a precise frequency.
- The shape of quartz crystals is typically hexagonal with pyramids at ends.
- For the circuit industry, they are cut into rectangular slabs.
- If you apply an alternating voltage to a crystal, it will cause mechanical vibrations. The depth of vibrations is determined by the cut and size of the quartz crystal.
- Quartz generates a constant signal
- You can use quartz crystals as filters in electronics.
- You’ll find quartz in radio frequency applications, and as an oscillator clock because it is highly reliable. You’ll also see it as a timing element in digital watches too.
- Quartz crystals are used to filter out unwanted signals in microcontrollers and radios. A basic filter is a single quartz crystal, but more advanced filters are made that comprise more than one crystal.
There you have it. The components you’ll find in a circuit board. If you’ve ever wondered what allows electronics to complete time-consuming tasks in just a few moments, now you know. Tiny electronic circuits are the foundation for all of our gadgets.