Breadboards: Guide and Tutorial

Breadboards can be an extremely handy and time-saving tool when building electronic circuits. In this guide and tutorial, I will explain everything you need to know about using breadboards and good breadboard practices, so that you don’t have to waste any time when building high-quality circuits. After you are done reading, you should have a fair idea of how to (and how not to) use a breadboard.

What are breadboards?

If you are a beginner to the world of electronics, you would have seen breadboards being used frequently. A solder-less breadboard (as opposed to the kind used in a kitchen), is a piece of plastic with a bunch of holes in it to help you connect and build circuits. They allow you to quickly connect, test, and disconnect components from a circuit while experimenting without you having to worry about splicing, twisting or soldering your wires/components again and again. They come in many sizes and colors, some of which are shown below.

Full Size Breadboard
Mini breadboard
Micro Breadboard (blue)

The reason for calling them breadboards is because of historical reasons. Before they existed, a circuit at home would be made on a literal breadboard, i.e. the kind used in a kitchen to prepare sandwiches, Nails made out of conductive material would be driven into the board and wires would be wrapping around them and spliced together to form connections and give direction. Components would be either tied or nailed to the board as well to hold them in place. This is how it would look.

Image (Courtesy of geotek from their retro prototyping instructable)

The holes on a breadboard are called pins and are used to connect components together without having to solder them. All pins in a column are connected to each other and all columns are disconnected form each other. The two pairs of rails running perpendicular to the central columns form individual connected lines. This is shown below.

Breadboard Connections Highlighted

The two pairs of rails on the extreme sides are used for providing power to the circuit. They connect to your DC power source’s power and ground lines. A lot of breadboards also have red and blue/black lines drawn parallel to these for visually indicating the purpose of each line (you are not forced to follow this, but it is good practice to).

Building Circuits using Breadboards

Building circuits on breadboards can be very easy, but doing it right is not obvious from the start. Let us start with a simple circuit where we need to connect two LEDs to a battery in parallel. Without a breadboard, this would look as follows.

Circuit Without Breadboard

The circuit looks messy despite having only three components and being a diagram on a screen (not to mention the nightmare of splicing all the wires together firmly). If we were to use a breadboard, here is how it would look.

Circuit with Breadboard

This looks far more structured, not to mention that it is quicker to build, test and then disassemble. The circuit without the breadboard would also not be as durable.

After reading this, you might be tempted to make a circuit that looks as follows.

Stranded Wire Circuit
Alternate View

Could you catch the error in the above image? It uses stranded wire rather a solid core wire. Stranded write is soft (it is made of multiple strands of conductive metal wrapped together, like a rope), in contrast to solid core write, which is hard and retains its shape (it is made of a single thick piece of metal write). Using soft core wire leaved your breadboard messy and cluttered looking. The extra lengths of the wires also reduces efficiency (this may not be visible in smaller circuits, but can be a problem in larger and more sensitive circuits). The same circuit as shown above, when made properly using solid core wires of correct length looks as follows.

Solid Core Wire Circuit
Alternate View

You can buy solid core wire in kit form (they are cut and bent already), or in spools (which is more economical).

Solid Core Wire Kit
Solid Core Wire Spool

It is also recommended to color code your wires, since it helps to prevent accidental connections (especially short-circuits) which can damage your components.

Connecting Breadboards

You might often find a single breadboard to be too small for the circuit your are currently building. In this situation, connecting multiple breadboards into a single unit can come in handy. To help with this, breadboards come with small bumps (marked with red) and slots (marked with blue) on their sides, as shown below.

These can slide into each other to connect the breadboards. If the breadboards need to be repurposed, they can also be disconnected by sliding them the opposite way.

Breadboards are not Permanent (mostly)

While breadboards are very good at fast prototyping and testing, they are not meant for permanency. A circuit on a breadboard can still be taken apart quite easily (in case of a fall or a bump) and is much larger than it needs to be because the components are not connected to each other by the shortest path. Let us explore some ways to make our circuits more permanent.

Perfboards

Perfboards are thin sheets made up of non-conductive material which have holes or “perforations” on them. These perforations are made at regular intervals and are ringed with conductive material (copper or steel). These perforations, similar to the pins on a breadboard, allow you to place parts inside. Unlike a breadboard, however, they are not connected to each other in any way and require the component to be soldered for a firm connection to be made. Shown below is an acrylic perfboard with copper rings.

Perfboard

A perfboard can also be made to custom dimensions (or shape) as per your circuit’s needs. A perfboard is a partial step in the direction of a permanent circuit, but a more permanent, rugged and compact solution is to use a Printed Circuit Board.

Printed Circuit Boards

Printed Circuit Boards (PCBs) are similar to perfboards, but allow you to exactly choose where the holed will be and connect them through direct conductive traces rather than wires. They also allow Surface Mount Components (components which do not have pins but are rather soldered to flat pads) to be used, which a perfboard does not allow. Shown below is a PCB.

Image result for PCB

The process of designing and manufacturing a PCB is very time consuming, however and must only be done when you are sure of the circuit and are ready to mass produce it. At the end of this blog you will find listed some ways to design your PCB and have it constructed. For a detailed tutorial on this, click here.

Conclusion

After reading this blog, you should be better prepared to use breadboards and make neat looking circuits. I hope you found this blog useful and learnt something new. If you have any questions or feedback, feel free to leave it in the comments down below.

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