Breadboards are a handy and time-saving tool when trying to build simple 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 waste any time building high-quality circuits. After you are done reading, you should have a fair idea of how to use (and how not to use) a breadboard.
What is a breadboard
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 repeatedly. They come in various sizes and colors, some of which are shown below.
They are called breadboards because of historical reasons. Before modern solder-less breadboards 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 from conductive material would be driven into the board and wires would be wrapped around them to give direction and spliced together to make connections. Components could either be tied down or nailed to the board to hold them in place. Shown below is a small example of how this would look.
The holes on a breadboard are called pins and are used to connect components together without having to solder them. All pins in a single column are connected to each other, while columns are disconnected from each other. There are two pairs of rails running perpendicular to the central columns that form individual connected lines. This is shown below.
By convention, the two pairs of rails near the edges are used for powering the circuit. They connect to the power and ground lines of a DC power source. Some breadboards include red and blue/black lines marked next to these for visually indicating this (you are not required to follow this, but it is good practice).
Build Circuits using Breadboards
Breadboards might make building cirecuits easy, but doing it right is not very obvious from the start. Let us start with a simple circuit where two two LEDs must be connected in parallel to each other and a battery. Without a breadboard, this would look as follows.
The circuit looks messy despite having only three components (and being a 2D diagram on a screen). Aside from this, the wires would have to be spliced together firmly, which seems like a lot of work for such a simple circuit. If we were to instead use a breadboard, here is what it would look like.
This looks far more structured, not to mention that it is quicker to build, test and then disassemble. The circuit on the breadboard is also far more durable.
However, we are still not done. After reading this, you might be tempted to make a circuit that looks as follows.
The above image contains an error that might not be too obvious at first glance. Could you spot it? It uses stranded wire rather than 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 leaves your circuit looking messy and cluttered. This may also cause wires to come out or wrong connections to be made because of poor visibility. The extra lengths of the wires also increases resistance to current flow (this may not be visible in smaller circuits, but can be a problem in larger and more sensitive circuits).
The same circuit, when made using solid core wires of correct length looks as follows.
It looks much neater, is far easier to debug, more reliable and provides less resistance to current. You can buy solid core wire in kit form (where they are cut and bent already), or in spools (which is more economical).
Another good practice is to color code wires. This makes it faster to find faults and in circuits and makes it harder to create accidental connections that may damage sensitive components.
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 needed because the components are not connected to each other via the shortest possible path. Let us explore some ways to make our circuits more permanent.
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, steel or sometimes even gold). 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 connections to be made. Shown below is an acrylic perfboard with copper rings.
A perfboard can also be made to custom dimensions (or shape) as per your circuit’s needs. It is a partial step from a breadboard towards a permanent circuit. 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 give greater freedom in where the holes/pins are placed and connect them through conductive traces on the board itself, 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 neither perfboards nor breadboards allow. Shown below is a PCB.
The process of designing and manufacturing a PCB is very time consuming, however and should 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.
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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