Thursday, March 07, 2013

Breadboard Basics 1: What Is A Breadboard? Structure and Overview

A ‘breadboard’ (shown below) is a blank board with holes drilled in a grid-like pattern. These holes are conductively connected in a certain way. The rows labeled with numbers (from 1 to 64) are conductive, with a non-conductive groove in the middle of the board.

A breadboard is a board that we can use to prototype / experiment with different circuits, and easily change them without having to solder anything. Breadboards are re-useable. Multiple breadboards can be connected together to form larger prototyping / experimenting areas. 

Components are placed on the breadboard. The structure of the breadboard is simple:
• The main central area of the breadboard is a block of two sets of columns.
• Each of column is made up of many rows.
• Each of these rows are electrically connected on a row-by-row basis.

For example, in the above picture, there is a chip on the breadboard. This chip has been placed on rows 5, 6, 7, and 8 using columns E and F.

If a connection is made to any point in position A5, B5, C5, D5 this is the same as connecting directly to the chip leg that is sitting in E5, because the row A5 - E5 is electrically connected.

There is a physical gap between rows E and F - thus, the two legs of the chip in row 5 are not connected. To connect to the upper right leg of the chip, its simply a matter of connecting to any point in position G5, H5, I5, J5.

Running along the outer left and right edges of the breadboard, we have the vertical busses. These are electrically connected vertically. These busses are often used for the positive and ground terminals of a power source such as a battery, as we might need to make many connections to these.

The diagram below summarises this structure.

Making connections along the same row in the same column block is meaningless, as these connections already inherently exist! (See diagram above).

Connections between rows are used to connect different chips and electrical components together.

Connections between the vertical busses to the rows provide power to electrical connections (only if battery terminals are connected to the vertical busses!)