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Nope - I'm not talking about automobile transmissions ...
I'll continue my series on the SPB16.2 new product features in the coming weeks.
I wanted to take a brief break and talk about, or more importantly learn from you, some of the basic techniques you use in constructing PCB library components. While this may appear to be a simple exercise in building parts for design entry, there are many facets to EDA libraries - symbols, physical views, BOM data, simulation models, mechanical details - to name a few. And then, there's the management of libraries - part request processes, version control, life cycle management, etc. Several products in the SPB product space can be used - Allegro PCB Design Workbench (ADW), PCB Librarian Expert (Part Developer), Allegro Librarian, etc. Web access provides some unique capabilities in accessing component data and the automation of library parts. The EDA Librarian experience is more vast than most designers know.
Libraries are near and dear to me - I "grew up" in the EDA world (back then Computer Aided Engineering - CAE) working for a defense contractor that utilized the Valid solution. I was the company's first "official" EDA Librarian. Sure, I constructed parts and simulation models, but I also worked with teams to develop best practices, templates, and techniques to increase my productivity. Some of these best practices are incorporated into the Cadence PCB libraries we supply today.
I also wrote an automated part generation program called GenPart when I joined Valid. It was considered "AE-ware" and freely provided to many customers. There were a few key FAEs who helped distribute GenPart to the customers, obtained valuable input to tune the program, and also assist with some of the algorithms. Mike Swienton was one of these FAEs and he continues to provide pre-sales support for the SPB team. It goes without saying, that with over 25 years of design and EDA industry experience, Mike is an recognized expert! GenPart became popular enough that Valid adopted the core code and developed a product called RapidPart which has eventually evolved into today's PCB Librarian Expert. I'm told there are still some pieces of GenPart that exist in today's PCB Librarian Expert product.
There are so many different areas of library development and management I'd like to chat about with you, and hopefully we'll explore those in future blog posts, but for this week, I'd just like to focus on the high level aspects of getting a part built for designers.
Specifically, I'm curious how many librarians use automated methods (e.g. PCB Librarian, ADW, home-grown utilities, etc.) versus the manual method in constructing schematic symbols.
Depending upon where our discussions lead, I'd like to explore additional aspects of library development in more details and see if we can share some best practices. There's a good chance some Cadence EDA library experts will soon join the blogging fray and take us into deeper discussions.
As always - I look forward to your feedback and continued discussion on this topic.
Being a unix user, we cannot use the import PDF option, bummer. But we are still using the Copy/Paste functionality to put the pin name and numbers in the Pin table.
Yep Mike - I really like your idea about copying/pasting datasheet data into Excel first. This allows you to do some data manipulation and then import into PDV. Nice method! Jerry
I have tried the import/export functionality to and from Viewdraw but the best approach was to generate the schematic symbols in PCB Librarian then export them back into Viewdraw. Obviously, with any translation there are issue which requires tweaks to be made on the other side but the cleanest approach is to build the schematic symbols in Part Developer and utilize the increased functionality / verification tools to speed symbol creation. I do import datasheets content into PCB Librarian but the only issue that I run into is that many vendor datasheets do not allow you to copy any information, include pin tables, from their PDF files and that is when I resort to using simulation models to extract pin lists.(of course after requesting updated datasheet with less security) When I import information from datasheets I find it easier to paste it into an Excel spreadsheet first to massage the data then copy/paste it into Part Developer. I am looking forward to learn all the functionality of Templates in Part Developer and I can only think it will make an already cool product better. - Thanks Mike
Hi Mike - good to hear from you! I'm curious if you imported any of the ViewDraw libraries into DEHDL via PCB Librarian? You're right about the verification capabilities - they really do enforce a correct-by-construction approach and that's why many librarians use PCB Librarian Expert. Do you import datasheet (PDF) content into PCB Librarian? Since you mention large pin count parts, this is one of the advantages of the product. For correctness of the symbols, I'd recommend using the Templates that are available in the SPB16.2 release of PCB Librarian. We're working on additional template capabilities in future releases, so that will make the correct-by-construction approach even more robust. Thanks again for your feedback! Jerry GenPart
I am relatively new to the PCB Librarian product, having used it for the past two years. We rolled out our Allegro DE HDL Library based on our DxDesigner library some time ago. I started using PCB Librarian Expert and I have to say I cannot live without it mainly because of its built-in automation and verification routines as well as its ability import and export multiple formats to assist in library development. Being a long time DxDesigner (Viewdraw) user where schematic to footprint verification was a multi-step manual process by placing schematic symbols on a schematic, compiling forward to Allegro and physically placing the component in the layout. On the Part Developer side, you can quickly and easily verify that your component footprint and schematic symbol are in sync and there are no pin mismatches as well as other related issues. I pretty much do all my schematic symbol generation inside of Part Developer and only push into Allegro DE HDL for tweaks.
The power of Part Developer comes to the forefront with large pin count devices where you have to split the schematic symbol into multiple symbols and generation / verification inside of one cockpit. I have used some component data via the web like Simulation models to extract pin lists to assist in schematic and footprint development but have not used the Cadence supplied libraries. I believe PCB Librarian Expert does have functionality to verify the correctness and completeness of symbols but I have not used them yet but plan on doing so in the future. We developed internal guidelines and online checklists to drive schematic and footprint development to verify that all the required information is built into the symbol and conforms to all manufacturing and test guidelines and it appears that Part Developer can be configured in a way to verify this type of information. One of the main goals of developing a library is being consistent and having guidelines in place is one major step of achieving that goal.
Well that’s my thoughts on the subject. - Mike