Solderless Breadboard

A solderless breadboard is a tool used in the field of electronic engineering to aid in the rapid prototyping of electronic circuits. It allows engineers to mount electronic components without having to solder them, which makes it extremely useful for temporary circuit construction. The system for mounting the components usually consists of holes for inserting the component leads, and metal clips underneath connected in rows, which forms the electrical collections. Breadboards of this type were available from as early as the 70s and 80s made of plastic and metal strips. With the emergence of digital integrated circuits (IC), these boards became very popular amongst computer designers who joined multiple boards together to build larger complex circuits.

In electronic engineering, a breadboard plays a vital role in the development of a circuit. It is usually the first stage of a circuit design, where the engineer may be calculating component values on paper, and testing the circuit on a breadboard. Once a breadboard circuit is perfected, it is usually constructed again on a semi-permanent system such as a strip board or prototyping board, where soldering is required. This provides an engineer with an insight into component layout, crosstalk issues, and a field test of the circuit. A PCB layout and construction usually follows the strip-board build, and since PCB manufacturing is the most expensive part of a design, it is last in the stage.

In industry, the popularity of the breadboard has vastly reduced due to the emergence of computer simulation software. Increasing numbers of component manufacturers provide software plug-in of their component so that engineers may readily use them in simulation software. With such powerful software, an engineer could design, test, and build the circuit in a virtual environment, including making the PCB layout. Breadboards are extremely popular in the education sector because they enable expensive components to be recycled, and saves having to buy expensive solder. It is also very useful where students may not be of age to use a soldering iron.

Electrical Connections

The quality of the electrical connections made by the metal clips within the breadboard is very critical. Usually, over time, the clips lose their tension, and sometimes there is oxidation causing poor electrical connections. This places a serious limit to the size of the circuit that could reliably operate using this medium.

Project Limitations

Due to the crosstalk between metal clips along the rows, this type of board is limited to low frequency projects. Therefore, radio and high frequency RF applications are usually not suited for this type of board.

How to use a Breadboard

Firstly, this is how to hold one to view it; it is amazing how even the so-called "experts" know very little of using one. As you can see the rows are numbered 1 to 30 and the columns are marked a through to j.

If you are just starting out using a breadboard then you should get used to visualising it with horizontally connected strips, that way when you start making semi-permanent circuits on copper strip-boards, you will be looking at the boards correctly with horizontally running strips.

A horizontal row consists of a group of five holes electrically connected from underneath by copper strips with spring clips. The holes are standard pitch and therefore a PDIP style package fits perfectly. The vertically drawn red and blue lines indicate the holes for the power rails. A large vertical copper strip internally connects these rails. Even though these holes are organised in groups of five, internally these groups are connected.

Jumper Wire Kit

A jumper wire connects one point on a breadboard to another point on the same breadboard or another breadboard. You could buy special kits with ready cut wires and plugs; however, a 0.6 mm diameter single core wire works best for the jumper wire connections and is cheaper if you get a large roll. You simply cut the wires to size and insert them into the holes.

A breakout wire allows you to connect a point on the breadboard to another point on a PCB. For example, if you are connecting a GPIO pin on the Raspberry Pi to a point on the breadboard then you will need a breakout wire. This type of wire has a female plug at one end to connect to the GPIO pin, and a male plug at the other end to connect to the breadboard.

Dimensions

These breadboards are usually 82 mm × 55 mm in size and just slightly bigger than a credit card. There is double sided tape at the back for permanent fixing into a plastic case. The great thing about these is that you can join multiple boards together to make a larger board, which is useful when your projects start becoming bigger.

With Regulated Power Supply

It is possible to buy breadboards with an integrated regulated power supply. They are usually a little more expensive but very useful in the long run. This is an excellent option if you are planning on a long-term career in electronics and might be building many circuits.

If you bought just a cheap board without a power supply, then it is possible to buy an add-on circuit, which plugs into the breadboard to provide power through an adapter.

Amazon / eBay

eBay and Amazon have the widest selection of breadboards, and I saw many for as little as £1.20 including postage. I ordered a couple on eBay and they promptly arrived a few days later all the way from China! Maplin also used to sell similar sized breadboards, and the cheapest one selling for a few pounds is the AD-100 Breadboard consisting of six holes in a row system.

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