Virtuoso Meets Maxwell: Completing the Virtuoso RF Solution Assisted Flow

16 Aug 2022 • 6 minute read

'Virtuoso Meets Maxwell' is a blog series aimed at exploring the capabilities and potential of Virtuoso® RF Solution and Virtuoso MultiTech. So, how does Virtuoso meet Maxwell? Now, Virtuoso platform supports RF designs, and the RF designers measure the physical and radiation effects by using the Maxwell's equations. In addition to providing insights into the useful software enhancements, this series broadcasts the voices of different bloggers and experts about their knowledge and experience of various tools in the Virtuoso IC-Packaging world along with the nuances of RF, microwave, and high frequency designs. Watch out for our posts on Mondays.

In my last blog, Getting Your Existing SiP File Into Virtuoso RF, I talked about the new enhancements in ICADVM20.1 ISR25 for Virtuoso RF Solution. At the end of the blog, I told you about the Fully Assisted Roundtrip flow, which includes importing SiP files that are compatible with the Virtuoso RF Solution assisted import flow into the Virtuoso platform. Let's examine how the Fully Assisted Roundtrip flow works in this blog.

To recap from the previous blog, What is the assisted flow? The assisted flow keeps and maintains all of the constraints and other data native to the SiP file while allowing updates from Virtuoso RF Solution to be incrementally updated to the original SiP file. Only the changes made in Virtuoso RF Solution are updated to the SiP file. The changes can include an update in the die footprint, a netlist change, an added SMD component, or an edit to the wiring.

In the previous blog, you saw how to use the assisted export to update the SiP with the remastered layout using the exported die footprint data. Remastering with the die footprint layout is what we call making the package design compatible with Virtuoso RF Solution. Then you updated the SiP file with the updated footprint.

Let's assume that the package designer has made changes to the module on this incrementally updated SiP file. At some point, you, as a Virtuoso designer will want to import the SiP file to see what changes have been made so that you can either visually analyze or use cross-fabric extraction to run an EM simulation or both.

Assisted Import from Allegro

This utility is used to import changes made in SiP if the package layout has become compatible with Virtuoso RF Solution. It also allows you to understand the modifications made and to reconcile with the existing library in Virtuoso RF Solution.

You need to open the latest layout, known as the reference layout, from the package library.

Once the layout is open, use the pulldown menu Module > Assisted Flow > Import Design Update.

Input the SiP file you want to import in the File Name field of the form. The Layout Reference section is grayed out. It is the cell that you have opened and invoked the Assisted Import from Allegro. The imported library is a staging library where you can perform a check against the source, Layout vs Abstract check, and other checks. The default name is importedLib.

After using assisted import from SiP Layout Option and before you create the layout in the reference library, you can perform additional checks.

Using assisted import from SiP Layout Option automatically opens the imported layout view. When you open the Annotation Browser, you see a new tab, AllegroLayoutImport. In the following image, you will see VRF Different Abstract and VRF Non Saved to Reference Library. Some Bumps have been moved in SiP Layout Option and are flagged in the AllegroLayoutImport tab when compared with the bumps in the reference layout. If you want to import the bump modifications made in SiP Layout Option, use the shortcut menu for VRF Different Abstract and update. If you do not update, the bump changes will be ignored when you create the layout in the reference library.

Before you do that, you should inspect the layout to compare the imported layout against the reference layout. To do this, use the pulldown Module > Assisted Flow > Compare with Reference Design.

In the Annotation Browser Misc Tab, you will find the differences between the two layouts. Open the reference layout, and you will see that the two layouts are in sync and they are superimposed over each other, so you see a halo of one die in background over the other.

Now that you have had a chance to compare and it is assumed that the layout is approved, click the AllegroLayoutImport tab in the Annotation Browser. Select VRF Non-Saved to Reference Library and use the shortcut menu to select the Create Layout In Reference Library option.

The Library Name and Cell Name in the form will be the same library that was used for the reference layout. If you are using DM, you should specify a View Name of the layout that will open a dialog to create a version of the layout. Else, you can specify a new name. The default value is layout_sip.

Now, you have completed a full round trip. You exported to Allegro as described in the previous blog, Getting Your Existing SiP File into Virtuoso RF Solution. In this blog, we described how to import from the Allegro platform. You can repeat this flow as many times as needed till all updates to the die bumps have been completed, and all analysis has been satisfied.

I hope you have found these two blogs useful and can now see how powerful ICADVM20.1 ISR25 is for the assisted flow.

Related Resources

Datasheet	Virtuoso RF Solution What’s New in Virtuoso
Free Trials	Virtuoso RF Solution - Module Layout with Edit-in-Concert Virtuoso RF Solution - EM Analysis Virtuoso RF Solution - Physical Implementation Flows

Datasheet

Virtuoso RF Solution

What’s New in Virtuoso

Product Manual

Virtuoso MultiTech Framework Guide

Virtuoso RF Solution Guide

Virtuoso Electromagnetic Solver Assistant User Guide

Free Trials

Virtuoso RF Solution - Module Layout with Edit-in-Concert

Virtuoso RF Solution - EM Analysis

Virtuoso RF Solution - Physical Implementation Flows

For more information on Cadence circuit design products and services, visit www.cadence.com.

Kerry Judd

Contact Us

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About Virtuoso Meets Maxwell

Virtuoso Meets Maxwell series includes posts about the next-generation die, package, and board design flow with a focus on reinventing and optimizing the design process to ensure that the designer remains a designer! Keep watching! Subscribe to receive email notifications about our latest Custom IC Design blog posts.