TI x Cadence | How to simulate complex analog power and signal chain circuits using PSpice® for TI

Hardware engineers are often expected to deliver results within tight project deadlines. Circuit and system designers must use every tool at their disposal to build accurate, reliably working designs that work well the first time. Meeting these demands, coupled with today’s changing office environment, means that circuit simulation and verification tools that can be operated from home or remotely are more valuable than ever.

We have found that engineers are reducing the prototyping and evaluation phase of their designs. In some cases, they will directly use the final printed circuit board (PCB), but everyone wants to reduce the risk of circuit errors. To this end, Texas Instruments, in response to the growing demand for high-performance, full-featured analog simulation platforms, has launched PSpice® for TI with Cadence, a full-featured version of the industry-standard OrCAD Pspice environment, making it easier to evaluate devices and simulate entire subsystems during verification.

For decades, Simulation Program with Integrated Circuit Emphasis (SPICE) has been helping engineers solve hardware design problems. There are three main use cases for circuit simulation:

• Device Evaluation. The performance of a specific product in a specific application can be measured, sometimes even before the actual device or application circuit is actually available.

• Validate designs. Building and simulating complex board-level and system-level designs before building physical prototypes gives engineers confidence in their circuits and reduces design time. Design validation includes the ability to simulate circuit operation under worst-case conditions and ensure that the product operates properly as parameters such as temperature, voltage extremes, and device tolerances change.

• Design debugging. If a design does not perform as expected, engineers often use simulation to troubleshoot problems or bugs in the system. SPICE simulation can also find and initially test circuit fixes without having to rework and test the actual PCB.

With PSpice for TI, the power of circuit simulation to accomplish these tasks can help you reduce development time and drive faster time to market. Computer-based simulation has inherent advantages. For example, with working from home more common today, using simulation means you can make significant progress on your project from anywhere. You also don’t have to wait for parts, PCBs, or lab equipment, just build your simulation test bench.

You can easily share circuit simulations electronically with other team members for larger system-level simulations or peer design reviews. You can also run more complex tests such as parametric or temperature sweeps, sensitivity analysis, or device tolerance analysis, which are expensive and time-consuming to perform in real-world situations.

Let’s look at an example in PSpice for TI. The simulation in Figure 1 plots the AC transfer function of a single-pole RC filter network while gradually increasing the capacitor value.

The resulting graphs are shown in Figure 2 , along with automated measurements of each graph's -3-dB bandwidth and gain at f = 1 MHz. Powerful analysis capabilities can greatly speed up design optimization.

Figure 2: PSpice for TI simulation and measurement results

Important note: Correct simulation results are based on the assumption that the device models are accurate and converge quickly (which means reaching the result). Fortunately, Texas Instruments has some of the most accurate, most convergent models in the semiconductor industry and is always working hard to develop new integrated circuits.

PSpice for TI provides schematic capture as well as analog circuit simulation. PSpice for TI is free to use and has many of the advanced features found in the commercial version, including automatic measurements and post-processing as well as Monte Carlo and worst-case analysis. Built on the latest PSpice version, PSpice for TI works offline, is compatible with projects developed in the commercial version, and offers an unlimited number of nodes and measurements when using Texas Instruments devices.

Speaking of Texas Instruments devices, along with the standard suite of device models, a complete library of nearly 6,000 Texas Instruments analog power and signal chain models has been integrated into PSpice for TI, allowing you to add Texas Instruments parts to your project with just a few clicks. No need to manually import Texas Instruments models, this rapidly growing library is automatically updated with the latest information on TI.com.

Most TI device models come with fully tested and operational design examples. In most cases, complete reference designs are also available that can be cut and pasted to quickly start designing and see device operation and performance. A few clicks in the tool place a device and open the associated reference design. Figure 3 shows one such design, which can be modified and simulated. The figure also shows the application’s dark mode and customizable color schemes, which help reduce energy consumption and reduce visual fatigue.

To make faster design decisions, the tool provides access to Texas Instruments product details and data sheets, as well as relevant queries from the TI E2E™ online support forum, which also features a library of tutorial videos.

Add SPICE simulation to your engineering workflow. Click here to download PSpice for TI and join engineers who are already using this powerful tool to shorten your design time.

For more online technical support, please visit the TI E2E Chinese support forum (e2echina.ti.com).