SIwave Component

SIwave Component Hello, this is Ibrahim Nassar with Ozen Engineering. In this demo, I will be showing you how to correct, assign, and define components in your board using the Ansys SIwave tool.

I will also show how to define components to terminate traces that exist in the board without any termination. So you can use the SI Wizard, which is basically an automated way to set up your model for signal integrity simulation. The SI Wizard does not consider open or unterminated traces.

So we will see in this demo how we can modify these traces and component placement so we can use this SI Wizard. Okay, I will start here with this opening SIwave. I'm using here the 2025 R2 release. I'm going to start a new project. I'm going to save it somewhere.

Now I want to also create a model here from scratch. I'm going to modify first the stackup. I'm just going to be creating a differential trace on a three-layer board or two-layer board. Please be sure to correct any mispelled Ansys product names as you transcribe, eg OptiSling should be optiSLang.

Then finish or done. Then here I can give it a name and give it a thickness. I'm going to give it like 0.8 millimeter. Okay, and now I'm going to basically copy and select all. I'm going to select this, sorry. Select by clicking, I'm going to select this trace and copy it and paste it here.

Okay, so now we have, you see here by default, knit one and knit two. Now I'm going to basically make layer two active and draw a ground plane. To draw a plane, we can select here draw a rectangle and just I like this.

Okay, I'm going to give this a name to be called ground, and we have knit one and knit two. Okay, so now let's assume we want to run that simulation, so we can manually create a port. To create a port manually here, we can just click somewhere and then click to the ground and ask.

I'm going to make it simple to be just a pad on the top layer, so I'm going to modify that to be like a rectangle with a width of 0.6 and update and hit ok. I'm going to place one here, and I'm going to place one here. Okay, unselect all, gonna basically delete the first one I inserted.

Gonna also insert Vs here. I'm sure. Inserted one here by mistake, gonna delete this.

Okay, so we have now these two traces, and it has a few pads here, so now we can select these pads to create a component, but it also would be better like to create another pad or via on the current plane, so I'm going to basically drop another via here, and I'm going to now edit the pad stack definition and going to create a new one and call it pad stack two.

Now I'm just going to make it, for example, to be a metal tool which is the ground layer. I'm going to change that to, for example, a circle with the radius of 0. 5. Update and hit OK. I'm going to place one here to be the reference for this pen and one here to be the reference for this pen.

I'm going to place one here for the reference to be this pen and one here for the reference here. Now, if we select the ground, you see these VIAS get already defined to be with the same NET name as the ground.

Here NET1, here NET 2. Now after we define it, we want to basically set up the simulation using the SI Wizard. The SI Wizard would not consider these open nets, so we have to terminate them with components. So to create a component is very simple with SIwave.

So you just basically select the pads or vias where the component will be placed. So let's select this one, this one, and this one, and this one.

Then you basically click on edit here, the properties window, and here I'm going to define it to be, for example, a die or a PGA, it doesn't matter, so let's call it a die, and it's placed on metal 1. I'm going to give it a name, my component, and therefore it's going to say U11, and as you see now, there's a component that got created, and it will be listed under.

Now I'm going to do it for the other side. I'm going to select this component, this pad, and this pad, and this pad, and this pad. Then click on edit and setup die on metal 1, my component 2. I'm going to call this U22, just to distinguish them. Now we have these two components defined.

Let's say you have a board, and this component came in, but you need to add different pads or the component got placed on wrong pads. You can simply modify them by just basically going to that component. For example, here, this one, I'm just basically going to delete it.

Or you can also use the optiSLang tool to create a new component. So, let's see how to create a new component. So, let's say I want to create a new component. So, I can select the component, and I can select the component, and I can assign the component to those three. So, let's let me undo this.

So, that's how you modify a component definition that already came in.

So again, we create the component by going to edit, die, metal 1, myComponent1, and U 11. Okay, so now, since these components are defined to terminate these traces, now we can set up simulation using the SI Wizard, which again gives an automated way to set up the model for signal integrity simulation, especially if you want to dynamically link it with Ansys Electronics Desktop to do TDR analysis.

So let's select that SI Wizard. Okay, again, it complains that there is no power plane. So let's define the power plane. It's easy to define a power plane here. If we go to Power Plane, we select which one we need it to be, and we just click on this arrow down, so now it's defined.

Now, if we go back to Single, you see the ground plane is marked with red. But it's not a necessary step here. Okay, so let's open the SI Wizard now. So again, you see now it's not complaining. We select which nets do we need to analyze, so they are already here, and hit next.

We define which one is the driver and which one is the receiver, so let's assume the driver is at U11 component side, and we hit next, next, next, and let's assume here that we want to link it to Ansys Electronics Desktop, and we hit ok.

Okay, so now we see, after we are done with the SI Wizard, you see the ports got created as a single-ended port, and you see like the nearby pad that is in the ground plane to be the reference for each port. So it takes basically the nearest pad as a ground reference.

And as you see here, now it's opening the Ansys Electronics Desktop to set up the model. So let me bring the other window here. So you see here, it's with the script to create this circuit to do the dynamic link between circuit and SIwave to perform eye diagrams and time domain simulation.

So here's the SIwave results, which basically contains the extracted S-parameters in SIwave and brought them here. In this demo, we set up this quick demo model, where we have an open-ended trace, which might happen in imported boards.

If interested in using the SI Wizard, you have to have these traces be terminated with components. Here I showed how you have them.

You can create a component and terminate them, and in case your board has issues with the component placements, has some missing pads or extra pads, so I showed you how basically you can modify the component definition by deleting it and reassigning it by selecting the pads.

So thank you for watching this demo, and I hope you find this demo useful. Please contact us at https://ozeninc.com/contact for more information.