Over the course of the past couple of years, I’ve been digging deeper and deeper into system engineering. Very frequently, that means using methodologies to deal with the complexities of designing across multiple engineering disciplines. Yet, that’s not always the case. There are many instances where the complexity of a design is high within a single engineering discipline. That’s certainly true of today’s multi-boards systems and wire harnesses.
In this post, we’re diving into the solution suite from Zuken, which include their CR-8000 suite and their E3.series suite. Let’s get into it.
System Planner Capabilities
With CR-8000, developing a multi-board design starts with System Planner. This application is really interesting because it provides many different views of a single model, including:
- Block Diagram View: Here, you start to conceptually place the major functional components of your system as blocks, like the processor, memory, image capture, wireless connectivity and more. You also connect these different components to one another functionally, even across different boards.
- Layout Diagram View (2D): With this two-dimensional view, you start placing electrical components across those boards. This includes things like connectors and other items with interfaces. Note, however, that this does not include the traces within the board. To do that, you use another CR-8000 application called Design Force. We’ll get to that in a moment.
- Space Diagram View (3D): Based on the Layout Diagram View, a 3D representation of the boards are built up. In this environment, you can import other 3D models like the electronic’s housing. In this context, you can check for interferences and clearances. You can also change the imported geometry to be transparent, so you can see the board inside.
- Lists / Countings: In this view, a complete Bill-of-Material is generated as you build your diagrams and layouts. There are many tools to sort and filter that list.
A critical point to note here is that all four of these views are pointing to the same underlying model. And there’s plenty of benefits to that. This application knows that each component has a representation in the Block Diagram, Layout Diagram and Space Diagram. As you change a component in one view, it gets updated in the other views. It also knows what components are connected to what components. All of the component’s characteristics are tracked and viewed in the BOM view.
From a systems perspective, managing all of this information across multiple PCBs is a boon, especially when it comes to changes and validation. In a trade-off analysis, you might want to experiment with the size of the board. Change it in one place and it updates in all of these views, including in the 3D view where you can see if the enclosure fits. Switch components out and not only do their footprints update, but you can do rollups for cost and weight in the BOM view.
Ultimately, System Planner provides capabilities to make sure you get the architecture of multi-board systems right and even optimized.
Design Gateway Capabilities
Next up in the process, engineers have to design the circuits functionally by developing technical schematics showing what is connected to what at a detailed level. This involves analyzing the design for signal integrity across analog and digital functions and components. Design Gateway provides a wide variety of tools to create schematics of multi-board systems, including:
- Signal Placement: There are numerous smart tools such that you can put the right signal into the right connection based on the information developed in System Planner or independently. In fact, there are wizards that help the engineer in figuring out the undesignated signals as a to-do list.
- Validation Tools: Design Gateway offers a wide variety of analysis and verification tools, including signal continuity, topology, analog waveviews, and more.
- Connectivity between Boards: This application allows engineers to do all of these things across multiple boards.
This is where the real engineering happens for PCBs. Design Gateway provides a wide variety of tools to automate the process and verify that designs meet constraints.
Design Force Capabilities
Of course, a major piece of developing PCBs is routing traces through the board. Zuken’s application for this activity is called Design Force, which is part of the CR-8000 suite. It supports routing for single boards, multi-board systems, and packaging chips into boards. For years, routing traces through boards was a 2D process. But in reality, this truly is a 3D activity because traces must not only be routed through a single layer but must go through other layers to connect to components. Inherently, it is a 3D process. Critical capabilities for this solution include:
- Constraints Browser: Users can track satisfaction of routing requirements through a Constraints Browser. For signal integrity purposes, some traces have a minimum and maximum run length. The Constraint Browser always keeps tabs on things like these run lengths, highlighting them in red or green to let the user know if that constraint has been satisfied. This actually works interactively, so while you route traces you can see if everything is satisfied.
- Manual or Automated Routing: You can route traces through the PCB in a manual fashion using a drag and drop process. However, you can also have the traces routed in an automated fashion. In fact, in some cases where the minimum run length hasn’t yet been satisfied, Design Force can add in an ‘accordion run’ to add length in a compacted space. Furthermore, layers can be added as necessary in an interactive manner.
- Placing Embedded Components: Design Force supports the approach to embedding components within the PCB layers. This changes how your route traces to the component and how the board is manufactured. Furthermore, you can move components from one layer to another in an interactive manner, which affects the traces as well.
Routing traces through a board isn’t a one-shot affair. It involves iteration and exploration while checking against many different constraints. Design Force provides a variety of tools and the right mix of 2D and 3D visualization to do the job.
Commentary and Analysis
It wasn’t that long ago that PCBs were seen as a commodity. It seemed as if the design software tools had caught up with the complexities of the boards. Fast forward to today, and multi-board systems present a whole new level of complexity that demand new capabilities. Zuken’s CR-8000 is one of the few suites of ECAD software that has added those new capabilities along the way.
Folks, that’s my take. I’m interested in getting your thoughts on this one. Sound off in the comments.