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0.1 Breadboard Fundamentals

Classic mini breadboard

A breadboard is the board you build a circuit on without soldering anything. Components and wires push into its holes, and the connections inside do the rest, so a circuit takes a minute to build and a minute to take apart again.

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The NULA MINI is sized to fit a regular breadboard.
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In this documentation you will learn:

  • What a breadboard is and why it is used
  • How rows and columns inside a breadboard are connected
  • How to place components and wires correctly

What is a breadboard?​

A breadboard is a reusable platform for building electronic circuits. Instead of soldering components together permanently, you push wires, resistors, sensors and microcontroller pins into its holes. Inside the breadboard are metal clips that electrically connect certain holes together.

This allows you to:

  • Quickly change connections
  • Fix mistakes easily
  • Reuse components many times

Breadboard layout​

A breadboard looks confusing at first, but the layout is simple. It has two areas:

1. Power rails​

The long rows on the left and right sides of the breadboard are called power rails. They are usually marked with a + (red) and a - (blue) line.

  • All holes in a single power rail column are electrically connected
  • They are typically used for VCC (3.3V or 5V) and GND
Breadboard power rails highlighted
Breadboard power rails highlighted
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Power rails are sometimes split in the middle. If you are unsure, check with a continuity tester before relying on one.

2. Terminal strips​

The centre of the breadboard is where most components go. It is divided by the middle gap, and that gap matters.

  • Each row of 5 holes is electrically connected
  • A row on one side of the gap is not connected to the row facing it on the other side
Breadboard central rails highlighted
Breadboard central rails highlighted with conncted holes marked in red
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The gap is designed so that components like integrated circuits can sit across it, keeping their pins electrically separate.

How connections work​

One thing to keep in mind before you start:

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Holes connected in the same row are electrically connected, so if you connect pins of the same component on the same row, they will be in a short circuit. For example, putting both legs of an LED in one row shorts them together and damages the LED.
LED with both legs in the same row, shorting it out
Both legs of an LED in the same row. This shorts the LED out and damages it.

Example of a correct connection​

To correctly use a breadboard, each pin of a component must be placed in a different row so that there are no electrical shorts.

LED with each leg in its own row
Correct LED placement. Each pin is in a separate row, allowing current to flow through the LED.

Here the LED has its two legs in different rows of the breadboard. One row goes to power through a resistor, in this example a GPIO pin on the NULA MINI, and the other goes to ground. Current then has to pass through the LED, which lights it safely.