USING LABELS IN KICAD FOR COMPONENT CONNECTIONS

To create circuits in a more efficient, organized, and streamlined manner, KiCad provides four primary methods for connecting components. The choice of method depends on the number of elements in the design and the designer’s preference for convenience during the process. The options include:

· Connecting via Tracks (Lines).

· Connecting with Net Labels.

· Connecting with Hierarchical Labels.

· Connecting with Global Labels.

CONNECTING VIA TRACKS (LINES):

As the name suggests, this method involves connecting components using tracks or lines. These lines can traverse the entire workspace, and they may even overlap other tracks while connecting components. An example is shown in Image 1:

Image 1. Component connection via tracks (lines).

If you choose this method, it’s crucial to ensure that lines do not connect inadvertently while moving them around, which is a common mistake during routing. See the example in the following image:

Image 2. Overlapping lines without proper connection.

In this case, the lines connected to pins 19, 20, 21, and 22 are not touching, which is a frequent error, as shown in the following image:

Image 3. Error in track connection.

The green dot between the lines indicates an unintended connection. This is a common error. KiCad won’t detect this as an issue because in some designs, such connections might be necessary. It’s important to always double-check the design to avoid such mistakes.

For the design shown in Image 1, the lines should not be connected to each other.

Note: In this example, blue lines are used to visually distinguish different functional blocks in the design, such as:

· Power Supply Stage.

· Comparator/Amplifier Stage.

· Arduino Nano Stage.

· Lighting Stage.

To connect components via tracks, select the Track option located at the top-right corner of the program with the following symbol:

Click the symbol and move the cursor to the end of a component. Click and drag it to the opposite end of the component you wish to connect:

Image 4. Connecting two resistors using a track.

CONNECTING WITH NET LABELS:

This method helps reduce the number of tracks needed between components, minimizing the risk of unintended connections while improving the overall visual clarity of the circuit design. Image 5 shows the same components from Image 1, but connected using net labels:

Image 5. Connection via net labels.

A closer view of the circuit illustrates the difference more clearly:

Image 6. Net label for the Lighting stage.

The black letters in Image 6 represent the net labels. These labels need to be repeated on the other side of the connection where they were previously linked by tracks. This allows the program to establish a connection. The next image shows the connection:

Image 7. Connection of D2_T1 at pin D2 in the Arduino Nano stage.

To create this connection, select the net label icon from the same toolbar used for track connections, as shown below:

Click at the point where you want to create the label, and a text window will appear, as shown in the following image:

Image 8. Net label properties window.

Enter a name to identify both ends of the connection, then select it, copy it, and press accept. This ensures that you have the correct label copied, minimizing transcription errors.