Some of you are Allegro Package Designer users, building single-chip or non-stacked multi-chip packages. Others of you are SiP Layout XL users, probably stacking dies or embedding elements into cavities, whether open or closed.

When you first install the 17.4 release on your machine, then, you will doubtless quickly see that these two products have been merged into one: Allegro Package Designer Plus. What’s the reason for this, why should you care, and how does it impact your environment and flows? Today, we’ll cover all those questions – at a high level only, I respect that every one of you is unique and may have slightly different issues. For those, please contact your Cadence support team and the experts here will help make sure you are ready to get the maximum out of the 17.4 release!

Why Are You Doing This?

We listen to you all the time. For some time, there have been questions about the specific tool you need for your projects. The two tools and two databases had different capabilities and structures, which can complicate moving between them.

By combining the tools into a single product line with options, Cadence can now provide you with a consistent core use model and data structure (more on this below!). This simplifies your use of the tool, as you should never need to remember two different ways to accomplish the same task based on the tool environment that you’re in.

Consolidating on a single database format and file extension means there is no longer a need for conversions and similar steps. The File – Export / Import –  MCM commands previously present in SiP Layout are now unnecessary. The SiP Finishing mode found in Allegro Package Designer is also rendered obsolete. The environment you use to edit your design is the same one that your manufacturing partners and customers will use to edit it.

There are still options on top of the product for advanced design styles such as silicon interposer design and RF elements. But, at its core, the environment you use will be the same for everyone, now.

I’m an Allegro Package Designer User, How Does this Affect Me?

If you are a 17.2 or 16.6 Allegro Package Designer user, the most significant change for you has to do with the management of your die components and layer stack-up.

Prior to 17.4, you could drive the thickness of your die components through the layer thickness of the cross-section layer for the layer the die was placed on. If you had multiple dies on the same side of the substrate, as we all know, they are rarely ever going to be the exact same thickness, material composition, or anything else (unless you’re placing an array of the same die, of course!).  

With 17.4, you will manage your die components’ attributes via the Edit – Die Stack Editor tool, the same way that SiP Layout users have been for years. Here, you will easily change the die orientation and attachment type, plus the thickness, adhesive material characteristics, and (flip-chip) bump geometries. These will be maintained with the design and automatically fed through to other tools, whether those are the 3D Viewer or the Sigrity analysis tools.

Additionally, you gain the ability to use the Die Stack Editor to manage your stacked dies, with bond wires intelligently pushing and shoving those of other dies stacked above and below it in the stack. Prior to 17.4, die stacking in Allegro Package Designer was not recommended and was a completely manual process. Now, you can sink the die (or die stack) into a cavity which will be automatically managed as you move or resize the die, the height of the stack is always known, and more assembly-related DRCs can be shown in real-time.

It doesn’t end here, either. You now gain access to the 3D Viewing technology that previously required an additional license, in the base product. Coupled tightly with the additional configuration data stored in the die stack objects, the view you see will be simpler and more accurate than ever before!

Be aware, also, that these data model changes will impact how you interact with some objects from SKILL. If you are a SKILL developer and have questions, whether they are about accessing die and die stack information, wire bond data, 3D information, or more, we are here to help you. I am confident that your SKILL code in 17.4 will be simpler to write, easier to understand, and faster to maintain. The advantages of a single data model!

These are the biggest areas to be aware of. A comprehensive walkthrough would be far too long for a blog like this. Our team is here to help you every step of the way.

What About Me, a SiP User?

As a SiP user, you already make use of the Die Stack Editor with every layout you create. The impacts to you, then, are significantly different.

The first such change is the file extension. While you can still save your design as a .sip file on disk if you want, the default will be to save as a .mcm drawing. This may impact your scripting and automation, and thus is an important item to consider. We encourage you to look at migrating to this file extension as soon as possible. When you start a new design, the default extension will be mcm, just as with your up-revved existing projects.

As a SiP user, you will want to select the SiP Layout (and possibly the Silicon Layout) option when running Allegro Package Designer Plus in 17.4. These will give you access to everything you used in 17.2, plus more. The Silicon Layout option replaces the Advanced WLP Option in 17.2. The menu containing these commands has also been renamed to match, but the features themselves work and are named consistently. You should not need to modify your scripts or SKILL code to continue accessing them as you did before.

Overall, the impact to you outside of the product name and database extension is less than to your Allegro Package Designer colleagues. The significant benefit for you is straightforward communication with those team members on a day to day basis.

Where Do I Go to Learn More?

Our product marketing team is actively sharing these details with many of you, but there is a finite number on the team. If they haven’t spoken with you just yet, and you’re eager to move up to 17.4, please reach out to them, or to our customer support team experts. We’re only too happy to help!