Components, terminals and their labels

When working with large circuits, using direct connections between different components of the circuit usually results in many wire cluttering. This may result in connection errors and makes it difficult to understand, debug or modify the design. The solution to this problem is to use terminals for connection. The video below shows how to wire up a design using labels. We can name the labels in any way we liked but sensible names make the schematic more legible and easy to understand. Essentially what we are doing by labeling a terminal is making a connection to another terminal with the same name, without placing a physical wire between the two objects.

The Power and Ground terminals are a special type of terminals. Although there is no reason not to label them; an unlabeled power terminal is assigned to the VCC or VDD net and an unnamed ground terminal will be assigned to net GND.

You can insert a terminal into the drawing area by choosing Terminal Mode then selecting DEFAULT from the Terminals list box as shown in the video below. You change the orientation of the terminal using the rotate and mirror buttons from the left bar menu.

To change the terminal name, double click on the terminal point and enter an appropriate name in the "Edit Terminal Label Window" as shown in the video.

Component Labels

You should see that all the components you have placed have both a unique reference and a value. The reference is set by a feature of ISIS called "Real Time Annotation" which can be found on the “Tools menu” and is enabled by default. Basically, when it is enabled, this feature annotates components as you place them on the schematic, saving you the time and effort of doing this manually.

You have full control over the position and visibility of component labels - you can change the values, move the position or hide information that you feel is unnecessary. The video below shows you how you can change the label orientation, name and even the size of it.

Also you’ll see how to create a component which is helpful when you don’t find the component you are looking for on the library.

 

BuzzNet Tags: Proteus ISIS