How PCB Board Works? an Ultimate Guide 2022

PCB boards allow you to easily connect many electronic components without soldering. Thanks to this, the same elements can be used in other projects. This solution is therefore perfect for learning electronics.

What is a PCb board? How it works? How do I transfer an electronic circuit to it? It will be clear after reading this guide!

 In this guide, you will learn how to use contact boards to build simple electronic circuits. These skills are useful when learning electronics, programming Arduino, or using the Raspberry Pi.

PCb boards , also known as PCb boards, allow for very quick construction of prototypes of electronic devices.

Why contact plates?

The electronic circuit consists of properly connected components. The current flows through the system and sets the whole device in motion. We often find PCBs with soldered elements. However, before we move on to such permanent assembly, it is worth building a prototype that will be cheap and will allow you to easily introduce changes.

Until recently, the best solution was to build "on a spider", that is, soldering or twisting the system "in the air". The second option was to create layouts from universal PCBs, on which you had to make all the connections yourself (e.g. with wires).

However, these solutions had their drawbacks. Therefore, the contact plates discussed here quickly gained popularity, which:

• they are durable - we can build different systems on one PCB for several years,

• they do not damage the elements - the same elements can be easily used in other projects (important especially for more expensive components),

• are easy to use - any prototype can be rebuilt in seconds!

How is the PCB board (schematic) built?

The universal contact plate consists of a plastic housing with holes spaced every 0.1 inch, or 2.54 mm (this is a common pitch for connectors, chips, etc.). There are special plates inside the housing (separated by plastic walls). They allow for easy connection of elements. The entire structure is covered with double-sided tape on the underside.

Contact plate - top, bottom, AND BOTTOM with double-sided tape peeled off.

Attention!  It's very hard to peel off a sticky plate! It's best not to use this option or attach the plate to the universal stand, which will always be at hand.

The plates outside the housing are visible below. However, we advise against removing them, as you can easily damage the plate - don't do it unnecessarily: How to place elements on the PCb board?

When building the electronic circuit, insert the element's leg through the opening in the housing and press it into the plate. Thanks to this, the current can flow further and reach the element inserted in another place of the same plate.

Below is an example of a simple circuit with a diode and a resistor. The current flows from the plus through the connecting cable, resistor and diode to the "minus" of the battery. The wires are stuck in different holes than the LED and the wire!

The assembled system in practice:

In summary, the plates in the contact plate can be treated as small, short wires that allow you to connect individual elements.

The main thing is to remember how the plaques inside the plate are connected. This is what causes problems when building the first systems. Many different contact plates are available for sale. In the beginning, we will deal with the two most popular types.

Medium PCb board (400 holes)

It is very popular, handy board that allows you to build most simple circuits. It works perfectly when learning electronics and Arduino. On the two extreme edges there are conventional power lines. Each of them is separated (the outermost lines are not connected). There are two columns in the center of the plate, separated by a recess.

The connections are shown below - each orange line means one, independent badge:

There are 30 plates with 5 holes in each column. This means that in each column we have room for 30 different signals, and we can connect up to 5 elements to each one.

It is a good practice to connect the power supply to appropriately marked power rails.

By means of elements protruding from the plastic housing, it is possible to connect several boards, which is useful when building more complex systems. The meaning of the indentation passing through the very center of the plate may also be puzzling. 

This is a clear demarcation of one side from the other. If the plates were connected there, the integrated circuits would not be able to be connected to the contact plates (their opposite pins would then be short-circuited).

Large contact plate (800 holes)

The second popular version of the contact plate is twice the size of the previous one. The connection layout does not change, as can be seen in the graphic below. For this reason, the construction of simple and complex systems on the PCb board is not a problem.

Sometimes there may not be a connection where the arrow is marked. The power lines will then be split.

It is best to test the line connections with a meter (in ohmmeter mode). In the photos below you can see that the signal flows with very little resistance (0.7 Ω) through the entire red bus. On the other hand, between the blue and the red bus, the resistance is very high (the meter indicates that the measured value is out of range), which means that there is no connection. So everything is correct!

Other contact plates (less popular)

There are also other smaller / thinner tiles on the market that may have a slightly different connection layout. Below we present the ones that were in our workshop. If someone comes across other PCBs, 99% of the overall connection layout will be the same. Sometimes the contact plate may have slightly different power lines.

Large PCb board

Everyone knows the concept of power. We see information about it on many products, including light bulbs and vacuum cleaners.

However, not everyone is aware of what this parameter is. Hence, many beginners do not know, for example, what power of the resistor should be used, which leads to damage to the element.

What is power?

Simply put, power should be considered as the amount of energy that flows in a given time. Energy can come in many forms. For example:

• mechanical energy (e.g. a speeding vehicle),

• electricity (e.g. stored in capacitors),

• chemical energy (in bonds between atoms),

• Thermal energy (related to the movement of molecules
  inside the body, its measure is temperature).

From the electronics point of view, a lot of problems are caused by thermal (or thermal) energy, because, as you know, too high a temperature of an element can damage it!

What is thermal energy manifested in?

Every object in our environment is a storehouse of such energy. We know this because everyone has a certain temperature. The higher the temperature of an object, the more this type of energy is stored in it.

Rubbing the hand, lighting the bulb, the flow of current through the resistor - all these phenomena are accompanied by an increase in temperature!

Sometimes it is desirable and sometimes quite the opposite. It is worth emphasizing here that the increase in temperature results from the transformation of one type of energy into another. Sometimes more than one type of energy is produced. For example, a light bulb consumes electricity and produces light and thermal energy.

Energy comes out of nowhere. There is no way to create it for free. Energy circulates in nature and is transformed from one kind to another. This happens with some loss of energy of a different kind.

The world is so arranged that nothing can be done without any loss. These losses are most often in the form of thermal energy. It must be drained from the device. Otherwise, the temperature rise will be so high that it may be damaged.

Examples:

• LED diode, which converts electricity into light, generates heat,

• a loudspeaker that converts electrical energy into acoustic wave energy, generates heat,

• An electric motor, which converts electric energy into mechanical energy, generates heat!

Why does the resistor get hot? Formula for power!

The heat can be generated additionally, for example during the lighting of LEDs or the operation of the computer processor. But that's not all! Sometimes elements are deliberately introduced into the circuit that can do nothing more - they only heat up.

Can you guess what this element is? It is a resistor, well known even to electronic beginners. Most often it is used to limit the intensity of the flowing current.

The role of the resistor is only to take power and convert it into heat!

According to Ohm's law, a certain voltage is deposited on the resistor:

If a current flows through an element and there is voltage at its terminals (ends), then we can talk about  power. These values are linked by a simple formula that is really worth remembering:

If we put the voltage U in volts [V] and the current  I in amperes [A] into the formula, we will get the result in watts [W] .