Before you start creating the part however, make sure that your parameters are set up the way you want by going to the Setup > Design Parameters menu. Once you’ve OK’ed the dialog box, it will open a new window for creating the footprint. In the New Drawing pop-up menu, select Package Symbol as the drawing type, and since we are going to create a simple fourteen pin IC, give it a drawing name of SOIC-14. To create a footprint using the pad that we just created, open up the Allegro PCB Editor and go to File > New. Building PCB Footprints to Load Into Your Layout Now you are ready to use this pad when building a PCB footprint. To finish the pad, go to File > Save As, and save it out to the location that you previously set up for your library padpath. This instructs Allegro to increase the clearance around the pad when the footprint is surrounded by a solid metal plane.Ĭadence’s Padstack Editor being used to build a rectangular SMD pad Also, note that we have specified oversized thermal and antipad values along with the regular pad values. For our example, we are building a 75 mil by 25 mil rectangle to use with a surface mount footprint.Īs you can see below, we are working in the Design Layers tab of the editor, and we have already input the values for our rectangular SMD pad on the “BEGIN LAYER.” Since this is a surface mount pad, we won’t be setting up any drill sizes or symbols, but we will add solder and paste mask layer data in the appropriate tab. Once the padstack editor is open, set the units, decimal places, and what type of padstack that you are going to build.
Macdoppler change footprint size windows#
Cadence’s Padstack Editor is a standalone tool, and although it can be opened from within the Allegro PCB Editor, it is simpler to use the Windows Start button to invoke it from the Cadence PCB Utilities. With our paths correctly set, the next step is to open the padstack editor. The Library Paths category in the Users Preferences Editor Within the library category of the path settings are two paths that need to be set for the libraries to work: the “padpath” and the “psmpath.” By saving or placing the pads and package symbols in the directories that these paths point to, you will have access to them within the PCB editor. This menu is used for multiple settings, but the ones we are interested in here are the library paths. In the picture below, you can see the Setup > User Preferences pulldown menu. But before we start that, we need to ensure that the right library paths are set up within the Allegro PCB Editor for the work that we are going to do. For our purposes, we are going to look at the process of building it in Allegro’s Padstack Editor. As with many of the design elements used in PCB layout, the padstack can either be imported or built. PCB Footprints First Start With a Padstackīefore we look at ways to create and load PCB footprints into Allegro, we have to first start with the padstack that will make up the foundation of the footprint. Here are some examples of ways to work footprints and libraries into Allegro’s PCB Editor so that they will be easy to find and use in your next PCB layout. On the other hand, working with an organized library for loading PCB footprints into your design tools is a real joy. Not only does the lack of an efficient library make finding the correct footprints difficult, but organizing new parts can be a real challenge too. Knowing the benefits of a well-organized library, it is always painful to me when I have difficulty accessing the parts I need in a PCB design CAD system. And since I’m the one who bought, arranged, and continually manages all of those books, I know exactly where each one is shelved whenever I want to revisit a classic story.
Reading seems to have lost a lot of its appeal in this digital age, but I still appreciate being able to relax with a good book in my hands. There is a room in my house that I value quite a lot because it has bookshelves built into the walls.
Macdoppler change footprint size how to#
Understand how to build and load PCB footprints into Allegro.įind additional tools and resources to help populate your footprint library. Learn how a good PCB footprint starts with a well-made padstack.
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