The current high-speed circuit design has reached the level of GHz, and the high-speed PCB design requires a comprehensive design of vias, packaging and wiring from the perspective of three-dimensional design theory to solve the problem of signal integrity. High-speed PCB design requires that Chinese engineers must have the theoretical foundation of electromagnetic fields, and must know how to use Maxwell’s equations to analyze the electromagnetic field problems encountered in the process of PCB design. At present, Ansoft’s simulation tool can dynamically simulate the signal integrity problem of PCB design from the perspective of 3D field solution.
Ansoft’s simulation tool
Ansoft’s Signal Integrity tools solve all design problems in one simulation:
SIwave is an innovative tool that is particularly well suited to address the power delivery and signal integrity issues that are prevalent in today’s high-speed PCBs and complex IC packages.
Using a novel approach based on hybrid, full-wave and finite element techniques, the tool allows engineers to characterize simultaneous switching noise, power and ground scattering, resonances, reflections, and coupling between lead bars and power/ground planes. The tool uses a single simulation solution to solve the entire design problem, reducing design time.
It analyzes complex circuit designs consisting of multiple, arbitrarily shaped power and ground planes, and any number of vias and signal lead strips. Simulation results are displayed in advanced 3D graphics, which also generate equivalent circuit models, enabling commercial users to adopt full-wave technology for long periods of time without having to use a proprietary simulator.
SPECCTRA Quest
Cadence’s tool uses Sun’s Power Plane Analysis module:
The Power Integrity module in Cadence Design Systems’ SpecctraQuest PCB Signal Integrity Suite is said to give engineers greater control over power plane analysis and common-mode EMI in high-speed PCB designs.
The product is the result of a development agreement with Sun Microsystems, which originally developed the technology to solve power problems on motherboards.
With this new module, users can calculate the target impedance of the power plane according to the system requirements; then consider the decoupling requirements based on the devices on the board, Shah said, and the wizard can help users determine the required decoupling capacitors for their designs. number and type; after selecting a set of decoupling capacitors and placing them on the board, the user can run a simulation program and analyze the results to find the problem.
Spice simulation program
The designer of the circuit system sometimes needs to make a detailed analysis of the relationship between voltage and current for some circuits in the system. In this case, transistor-level simulation (circuit-level) is required. The circuit models used in this simulation algorithm are the most basic components. and single tube. During the simulation, the I/V relationship of each node is calculated according to the time relationship. This simulation method is the most accurate of all simulation methods, but it is also the most time-consuming.
SPICE (Simulation program with integrated circuit emphasis) is the most common circuit-level simulation program. Various software manufacturers provide different versions of spice software such as Vspice, Hspice, and Pspice. The spice simulation algorithm.
SPICE can perform nonlinear DC analysis, nonlinear transient analysis, and linear AC analysis of circuits. The elements in the circuit being analyzed may include resistors, capacitors, inductors, mutual inductances, independent voltage sources, independent current sources, various linearly controlled sources, transmission lines, and active semiconductor devices. SPICE has built-in semiconductor device models, the user only needs to select the model level and give the appropriate parameters.
EMC-Workbench of ZUEKN
The company debuted the latest version of its virtual prototyping product for use in its “Board Integrity” design process. The new product, Hot-Stage 4, has revolutionized the high-speed PCB design process by introducing a consistent, constraint-driven engineering environment.
This new product includes a spreadsheet-based constraint manager, automatic constraint wizard, “what-if” editor, embedded router with in-circuit simulation, verification, and EMI and thermal analysis capabilities.
Hot-Stage 4 addresses signal integrity, EMI, thermal, and manufacturability issues in today’s high-speed design process, providing design engineers and layout engineers with a way to correct their designs. Engineers enter constraints, and the tool automatically synthesizes a design that meets the requirements. Constraints are managed in a Windows-like environment. Its tree browser makes it easy to design indexes, while spreadsheet software can edit electrical constraints and display illegal constraints, all in one interface, thus reducing redesign, production costs, and product shortening time to market.
A stand-alone option, Hot-Stage EMI, further enhances the capabilities of this product with a full-board scan that quickly checks for radiation effects. This is said to be an effective method for judging radiation sources, allowing the user to know the EMC performance of the entire board in advance and helping to avoid problems caused by poor EMC performance.
Mentor’s ICX Signal Integrity Solution
This is the first PCB signal integrity tool to support SPICE, IBIS and VHDL-AMS in a single simulation environment: ICX 3.0 addresses the signal integrity and timing challenges caused by the higher clock frequencies and signal edge rates of high-speed digital PCBs, Make simulation more efficient and accurate. The solution will allow system designers to reduce design time and improve system performance, while also giving IC manufacturers more options for modeling device behavior. In addition to ICX 3.0, Mentor Graphics also released Tau 3.0 products, the latest version of the company’s board-level timing solution, now with a higher degree of integration with ICX.
ICX 3.0 and Tau 3.0 have strong usability, a variety of interfaces, and a number of functional improvements to improve high-speed design performance. ICX 3.0 provides enhanced interfaces to the company’s Expedition and Board Station families of PCB design tools, including bidirectional interfaces for the new ICX and Expedition products, allowing users to leverage the full capabilities of ICX tools for signal integrity design and verification .
The symbol timing analysis function integrated in Tau 3.0 provides a solution to the timing verification needs of board circuits. Tau 3.0 is a major update to the Tau Simulator/Analyzer, with enhanced usability and more specific information retained when analyzing.