When designing a new piece of hardware or writing a new piece of software, you only have so much time to build and test new versions to get your product working. Making changes and repeated testing can be extremely time-consuming, especially when trying to diagnose simple problems.
Just like with software, a simple design problem in your PCB can ruin your board’s functionality if gone unnoticed. So what is the best way to get to an end-user prototype without repeated redesigns and rebuilds? When you incorporate a simulation package into your workflow, you can diagnose and quickly correct straightforward design problems before your first prototyping run or as part of your overall prototyping and testing process.
To Simulate or Not to Simulate?
Building a simple functional prototype usually starts with an evaluation board (if one is available for your components) or with a two-layer prototyping board. This allows you to arrange components and test the basic functionality under controlled conditions. These conditions may not reflect the real way in which your board will operate, although using a prototyping board is a great way to test some basic functionality.
The drive to get a copy of your board into your hands and begin testing is only natural. Perhaps there is a perception that you will get a better idea of the performance and functionality of your design if you can hold it in your hands. While this is certainly true when you need to examine and test end-user prototypes, you can cut down on your prototyping costs by working with a circuit simulator package as part of your PCB design software.
The design phase for your PCB requires taking your functional prototype off an evaluation board and recreating it in your design software. The goal is to move ever closer to an end product. However, when your design is recreated as a PCB and is running at full speed, its performance may not match the actual state of your device on an evaluation board. You might be tempted to order a prototype as soon as you finish your design. Instead, you’re better off using a simulation package and looking at a virtual prototype.
Simulation and analysis ought to be a vital part of your prototyping process.
The Advantages of Virtual Prototyping
Working with simulation software specifically built for circuit analysis allows you to implement a new step into the electronics product design process: virtual prototyping. With PCB design software, your layout represents a virtual model of a completed device; it is much more than just a blueprint for traces and components.
Before powerful simulation software was widely available, and before the required computing power became affordable for everyone, product designers were forced to analyze every portion of their devices on paper, manually calculating every electrical characteristic while trying to account for electronic and dimensional tolerances. With simple devices, this is just fine but many analysis activities quickly become intractable when working with complex devices.
If you opt to order prototypes from a manufacturer, each redesign and testing run will incur some additional costs and will take time to fabricate and deliver. Once you receive your board, you’ll need to assemble and test it manually, which takes significantly longer than working with circuit simulations.
Virtual prototyping with simulation software allows you to identify and address signal integrity, thermal management, and even manufacturability problems in your board before you order prototypes from a manufacturer. You can reduce the number of prototyping runs when you use a circuit simulator that takes data directly from your designs.
Verifying signal integrity in a functional prototype
Limited Functionality Rapid Prototyping for Product Design
Using a circuit simulator nicely complements rapid prototyping for product design as it reduces the number of redesigned boards you need to order from your manufacturer. However, circuit simulations do not always provide the same insight as testing an actual prototype. Depending on the functionality being tested, such as EMI susceptibility, power integrity, or signal integrity in a multi-board system, it is difficult to perfectly account for every variable that can affect the system.
With more complex products that include a diverse array of capabilities, one common practice is to develop rapid prototypes that demonstrate only one function or a limited subset of related functions. These can cost less to produce, take less time to test, and problems are easier to isolate and correct. This makes it easier to understand the behavior of each portion of a product in an environment that more closely matches its intended operating conditions.
You can use simulations to examine each functional block of your overall product to get an idea of its performance, as well as determine the best course of action for redesigns. In complex systems, even when broken into functional blocks, a proposed redesign could be a stab in the dark. Circuit simulators allow you to directly compare proposed redesigns with your current design before you order a new prototype.
Look no further than the OrCAD PSpice Simulator if you’re looking for the best circuit analysis package that is specialized for PCBs. This powerful simulator integrates with thousands of components and includes pre and post-layout for analog and mixed signal devices. The circuit optimizer can help you improve the performance of your device before you produce a prototype.
If you’re looking to learn more about how Cadence has the solution for you, talk to us and our team of experts.