Nice to see Cadence continually trying to improve their in-tool DRC checks and not relying on third party tools to get the job done. Now that Mentor Graphics has grabbed VALOR I can see Cadence spending a considerable amount of time trying to get “manufacturing quality” checks directly in Allegro.
Here is a snapshot of the new DFM related features included in Allegro 16.5
follow link here
I know this series is very late, but the summer was much busier than expected. Well as they say, better late then never. So here it goes. I have decided to evaluate the different CAD tools that we use here at Vision Circuits based on specific topics that are critical to designing a board. This is based on my experience and feedback from the Vision team.
As the title mentions, the first evaluation will be of the libraries (footprints only). Libraries is a very important part of PCB design. There are thousands of parts developed by different manufacturers with different specs. Building a library is not necessarily difficult but great care must be taken as one erroneous footprint on a board can mean countless hours lost troubleshooting in the lab. This is why CAD tools must have a good library manager to facilitate the process.
The first thing that comes to mind is the number of files needed to build a component. You need a pad or multiple pad files, the editable part, as well as the read only part. If you are using a 3rd party schematic tool , you will also need a text file. This is without counting the files you may need for other features such as shapes or flashes. This can get very chaotic if not well organized. Creating the footprint is a fairly simple task in Allegro. There is nothing fancy, no feature that make it stand out but there is nothing wrong with it either. It’s fairly intuitive and easy to learn for beginners. The component wizard is good but would need a revamp as many new footprint types exist today. I must say that the measuring feature is great and probably one of the best when compared with other tools.
For a high end tool, I am disappointed in the lack of a proper library management feature. Allegro’s library needs a good process in place otherwise it can become chaotic.
I give it 2.5 out of 5 stars
Expedition has a completely different strategy for library management. Parts are still individual files but are in a structured folder which, when viewed using the library manager, is shown in a very well structured format. Included in the library manager is a padstack editor that lets you create and manage all the holes , pads and custom shapes easily. The footprint editor is quite good as well and has all the features to build your component. The wizard is OK, not very versatile but it helps speed things up a bit . It can also be a bit difficult sometimes to do some simple task such as removing pins for example. It’s a very powerful tool but you do need to know the tricks as it is not as intuitive as other EDA packages. Once the footprint is created you simply need to assign it to the part. The measure tool is quite good as well in this tools. One large issue is the fact that the padstacks can’t be locked after creation and can easily be modified at any time. If the user is not careful he could mistakenly modify padstacks and they would automatically be updated on all the assigned footprints without warning. This makes editing padstacks easy but risky. A simple “lock” feature would solve the issue.
Overall the library manger is quite good. There is however some features that could really be improved when it come to some of the most simple task. Expedition is a tool that is hard in the beginning, but the more you work with it, the more you learn to love.
I give it a 4 out of 5 stars
A PADS library consists of 4 files. There are really only 2 that are important for footprint creation. Decals and Parts. Decals are the actual footprints, and parts are the component details that the schematic needs to forward annotate. In the part, you can define several decals, pin details and swapping options. The Library manager is very easy to use. You can add, copy from one library to another very easily. Building the decals is not very difficult, but you will need to create specific views as changing layer display is very time consuming and there are a great number of unnecessary layers. The component wizard has just been improved and now uses the IPC naming conventions and builds decals per IPC recommended land pattern. This is the only tool that offers this and I must say it is a great value added to this tool. The biggest disappointment is the fact that there is not a measure tool available other than point to point. This makes creating parts that are not symmetrical extremely difficult. It is hard to comprehend how a CAD tool can be lacking a solid measuring feature. The software also has some great features that are not offered in other tools such as auto-renumber of pins and “associate shapes with pins” options.
This is really a great tool for library management. The features are great and the addition of the IPC land patterns give it a real advantage over the other tools. It is really too bad there is not a proper measure tool. Otherwise this would be one of the best library tools out there. Really do not understand Mentor decisions here.
I give it 3.5 out of 5
The graphical interface of this tool is the first thing that I noticed. The software looks new and fresh compare to other CAD tools. The library consists of one single file. All CAD tools should follow this model. It makes transferring and sharing your library a breeze. Copying components from one library to the next is a simple copy and paste function. In general, the Library manager could not be much better. The wizard has many component types to choose from and is very easy to use. All objects can be modified using the property option which gives the designer lots of flexibility. The measure function is very good as well and provides all the necessary information (center to center, edge to edge). On a critical note, there are no padstack libraries and all the padstacks must be built from scratch each time, for each part. This is time consuming and increases the risk of errors. There is however and option to apply padstack changes to all components in the library. Not really sure if this is a good thing or a bad thing as it can really mess up a library if not used properly but can also be a very powerful feature. A downside to this tool is that there are no pre-defined assembly layers. There is a work-around but, by default all components should have assembly layers defined.
Overall this is really a great tool to build libraries and rivals (even surpasses in many ways) the “higher end” tools.
I give it a 4.5 out of 5
Libraries are taken for granted and it shows even with the CAD software companies. The time spent in adding feature on the layout side of the tools is far superior to what is spent actually developing a great library manager tool. This is unfortunate as libraries play a major role in the development of a product. Hopefully in future upgrades we will see some improvement to the CAD libraries.
Good communication between designers and engineers is key for a successful project. This is usually quite simple if you can work side by side with the customer. But we all know that this is not always possible. Often we need to work with customers that are in different offices and many time in other cities. The good news is that with today’s technology, we have the tools and capabilities to make this a much easier task.
One of the tools that we have invested in here at Vision Circuits is Glance. A simple, easy to use screen sharing tool. We have been using this tool for several years now and it has proven to be very effective. Glance’s strength, and the main reason we chose this tool, is the simplicity of the software. There is practically no setup needed by the customer and the software is never restricted by firewalls. In a matter of minutes you can show your screen to the customer and discuss any design issues on the fly. Glance is available in yearly, monthly and even daily subscriptions.
We will be starting a new series called “CAD in Review” focused on providing a clear, experienced review of the most popular CAD tools out there. We use the layout end of these tools day in and day out on some of the most cutting edge designs out there and we make the most out of each CAD package. Some are great, some are just good, and some are downright awful. We will review the learning curve, the features, the ease of use, the stability, value for the price, quality of support and many more aspects of each package. If there are any other aspects you would like us to provide feedback on please let us know.
Stay tuned, Cadence’s Allegro is first on deck this summer.
I have never been a huge fan of the Macrovision FlexLM security software that CAD software companies such as Mentor Graphics and Cadence use for their tools. Service bureaus need to manage multiple licenses in several different CAD tools so dealing with dongles can prove very challenging.
This is why I was very pleased to see the new online licensing system created for the Altium Designer suite. Once the license is registered any user that has Altium Designer installed on their computer can connect via an online server to authenticate their software. This means a much more streamlined setup and maintenance of CAD licensing. It also makes it much simpler to work at a customer’s site whether it is for a full day or simply for a meeting. The license is accessible for on the fly modifications and reviews. It also allows designers to work from home without needing to carry dongles with them.
I was very impressed with Altium’s way of thinking and hopefully other CAD tools will follow suit with this type of licensing. You can learn more about Altium’s line of CAD software by visiting their website at www.altium.com.
Since the Vista operating system Microsoft has been trying to push their sidebar and Windows gadgets. I don’t know about you, but I haven’t found much use to any of them. Lately I decided to give it another go and see if there was anything interesting out there. Well I came across a gadget called “Unit Converter” created by GadgetWE which is pretty nice. The gadget has a nice sleek look and can be made bigger or smaller depending on whether you are using it or not. What’s more is that you do not need to enter a value and press an “enter” or “convert” button, it converts the value on the fly and in both directions (from mm to mils or from mils to mm).
Seeing how libraries and mechanical drawings have pretty much all gone metric and layout seems to stick to imperial we are needing to convert more and more often and this little gadget has proven quite handy.
Look up the Unit Converter by following this LINK.
There are many reasons a business might chose to blog. For Vision Circuits the main motivation is to extend information to our customers, suppliers and other PCB Designers around the world. A blog is a great “living” platform that allows people to share, communicate, poll and educate others around them and on the topic of PCB Design there are too few available resources.
We hope to share with you as much as possible, maybe once a week or so. Here is what you might see on our blog:
We hope this will be an engaging medium for readers and our team alike.
- VC team