Estimated reading time: 4 minutes

Connect the Dots: Choosing the Right CAD Tool

Every profession has its tools. Painters use brushes, mechanics have socket wrenches, and parlor magicians have long sleeves. For PCB designers, the tool of the trade is CAD software. Designers spend hours, days, or weeks in their CAD tool for each circuit board design. They thoroughly check each connection, plot every through-hole, and carefully place components. This process inevitably reveals that not all CAD tools are created equally.

Each designer has different needs from a CAD tool. Some only produce a few designs per year, which means there is limited opportunity to learn the ins and outs of complex CAD software. Others constantly work on PCB design, moving from one design to the next with barely enough time to catch their breath.

How can designers find the right CAD tools to fit their design needs?

Making Sense of the CAD Tool Ecosystem
A quick search reveals that the world of PCB design is flooded with tools, but evaluating more than a handful can be daunting. To narrow the field, examine some basic criteria.

Price
For those who design PCBs intermittently, high-priced tools may not make sense, and there are many low-cost and free CAD tools available. When evaluating free tools, pay close attention. Some will be open source or community-run projects, and while the philosophy behind them might be attractive, make sure those tools are still being actively maintained and provide user support.

Some low-cost and free CAD tools are funded and developed by PCB manufacturers. They produce tools that specifically work with their manufacturing process, which can be great if a designer has a specific manufacturer in mind for their design. However, this choice can also lock in a specific manufacturer path, so choose carefully. Does the manufacturer’s CAD tool cost money? If so, how much? Can it provide Gerber files?

Commercial packages can quickly become expensive. There are a few CAD tools available that charge a monthly subscription price, but most offer prices ranging from about $75 all the way to over $2,000. Pay attention to the limits placed on products with multiple tiers of pricing and be particularly careful not to get caught in a "freemium" trap, where a piece of software seems great until that really important feature is locked behind an expensive paywall.

Component Libraries
CAD tools are almost always customizable with libraries full of parts and components. It is important to be sure that the tool being considered can support the parts required by the design. Many tools like to brag about the size of their parts libraries, but don't be fooled by a big number.

A typical designer might need a library of about 10,000 parts, but when looking at the library offered by a CAD tool, confirm that the requisite parts are available. Look for commonly used parts and check whether the tool comes with proprietary libraries or access to specialized libraries required for the project.

No matter the CAD tool, eventually designers end up creating components themselves. Make sure the tool provides the capabilities needed to both create new components and add them from external sources.

Complexity
CAD tools exist to tackle the complex problem of designing PCBs. Unfortunately, it's inevitable that the CAD tool will itself be somewhat complex, but even so, it should be intuitive and easy to use as it is.

Ease of use is an area where less expensive, open-source software tends to lag behind. If price is an important factor in the decision-making process, the result can be a balancing act between price and usability.

Help and Documentation
There will come a time when expert help is needed to move a PCB from design to manufacture. Make sure that the CAD tool provider offers user support early in the process. If there is a phone number for support, call and ask some questions about the product. Live support can come in very handy with more complex designs.

CAD tool software providers should make their documentation available online. Quality documentation can be a huge help to designers who need questions answered in a hurry. Even YouTube tutorials and user forums can offer solutions to common issues with a CAD tool.

Checking the tool’s documentation and looking for video tutorials can also help you evaluate a CAD tool when deciding what to use. If there are too many people reporting problems, that might mean the tool is too difficult to use. Likewise, a YouTube tutorial that takes the viewer through too many convoluted steps can be a red flag toward usability.

Additional Considerations
CAD software is almost always highly customizable with design rules, favorite libraries, shortcuts, and modules to increase productivity and make the design process personalized and special.

Pay attention to limitations, such as board size, and the number of pins or layers a tool can support. Watch for limits on minimum component pitch and the supported sizes for traces, spacing, and vias. Once you have narrowed the field, download the CAD tools that look the most promising and try them out. Fifteen minutes or so should be enough to tell whether the tool is intuitive and will fit your PCB project.

CAD Tools Must Be Easy to Use

The most important part about choosing a CAD tool, though, is that it shouldn't make designing too much of a chore. You want designing to be productive and efficient and, in the end, maybe that's the most important element to evaluate when you're trying out different tools.

This column originally appeared in the October 2023 issue of Design007 Magazine.