BBS on Mentor2013 China PCB technology, Mentor for complex PCB design challenges, this paper expounds the three dimensional (3 d) PCB system design technology, multiple plate system design, advanced packaging and collaborative design method, by reusing concept, enhance the efficiency of the design and the design method of power integrity, etc.
The challenges of the PCB design
In automotive electronics, computer, consumer electronics, industrial, military/aerospace and communications, the complexity of the PCB design has been increasing, the signal integrity and power integrity, manufacturability, cost, and reliability factors, as different present a bigger difference in the field of application.
Mentor JamieMetcalfe market development manager, points out that increase also reflected in the design complexity, PCB metal layers in 2007 from 16 layer down to 14 in 2012, down 12%; Area from 90 square inches to 58 inches square, 35%; Number of wire per unit area increased from 212 to 212, up 15%.
Increasing design complexity make Labour structure has changed a lot, including engineer position and quantity. Design team had only basic design, layout engineer and project manager, is now increased by the FPGA, machinery, system architecture, SERDES, thermal management, such as signal integrity, power integrity engineer, and they need to work together.
In addition, the original PCB centered design pattern, also turned to the IC/FPGA, PCB, the system module based way of system engineering design.
The 3 d PCB system design technology
Electronic products smaller and more versatile, design constraints, more strict, factors such as wiring density and higher reliability, increased the complexity of the PCB design.
Mentor DavidWiens business development manager, said: "when faced with PCB thicker, prototype production costs are higher, more time for many times, manufacturing yield more low, the designer should consider using three-dimensional PCB system design technology, it will be a PCB under a main trend of the system design."
Wiens mainly introduced the three dimensional PCB system design process. First, to create a unified support a wide variety of applications of 3 d components library, the library must be able to support simplified and grid (Mesh) setting. At present, the Mentor, the three-dimensional device library contains more than 400 device models.
Of course, users can also create new devices. In this way, can build 3 d model for electronic components, to increase the device model of the enterprise, and map it to manufacturer's device type, the user simply input element data list of parameters.
The second step is the three dimensional design and DRC (design rule checking). Through the Expedition 3 d solutions, three under two kinds of images can be displayed in the same window, and can realize element. Three-dimensional 3 d compilation of the compilation and analysis including wiring, and the analysis of dynamic and static test of three dimensional constraints and can choose detail or simplified three-dimensional modeling. This technology could help identify possible existence of a variety of problems, for example, components, components and between the shell and the radiator, whether there is interference in three dimensional space.
And then the three-dimensional vibration test. In the reliability problems caused by the design sketch, vibration is ranked second on the temperature after failure factors. According to the U.S. air force announced defense electronics system failure caused by environmental problems, a report, the temperature problem caused by the failure is as high as 50%, vibration factors accounted for 20%.
Wiens quoted EdmondL Qualmark companies in the United States. Dr Kyser survey data indicates that the first year after delivery, due to a design flaw field returns for all direct costs (fieldreturns), each new design to a maximum of $440000.
Next is the acceleration of higher life cycle test (HALT); Three-dimensional modeling and solution; Strong before and after processor can create a virtual prototype.
Wiens said of many GHz interconnection in the design of three-dimensional simulation analysis, the three dimensional structure of signal integrity will cause great influence, while the existing 3 d simulator for the engineer's professional can demanding, Mentor scheme does not. Specifically, analyze the three-dimensional structure and s parameters of the model is set up; Will be added to complete its interconnection description; Analysis of interconnected; The use of HyperLynx tools layout before and after the signal integrity simulation and analysis. For many GHz complete SERDES channel design, 2 d and 3 d simulation and modeling of hybrid can provide accurate speed.
Then is to upgrade the electronic and mechanical design (ECAD/the direction of MCAD). After designing and manufacturing departments, automatically update database may change depending on the situation.
Finally the three dimensional thermal analysis (FloTHERMXT). Focusing on the PCB design from concept to all validation/prototype stage.
Design reuse can improve efficiency
In electronic design, many engineers or designers to design reuse is often a lack of motivation, they don't want to be by modifying the results of other people to complete the design, because they think the design of reuse other people cannot show their own ability and value, and management of reuse modules may be trouble, such as store and find out the reusable data, etc. As a result, designers will always want to achievement is designed according to the "original" out of his thoughts.
But executives consider is how to shorten the design cycle, reduce costs, improve yield and product quality, reduce component variations and improve purchasing advantages, in the design of the low risk, to meet customer demand.
Designer is necessary to realize, in fact, the vast majority of plate element by reusing module design, this is mainly for improving the efficiency of design considerations.
Application engineering manager in China Mentor Liu Xuefeng pointed out that in order to change the idea of stylist original, light and heavy use, the enterprise culture must encourage reuse design, EDA tools also need to eliminate some of the technical barriers, such as extracted from proven design reuse objects; The logic, constraint and layout package to reuse objects; Support informal and formal reuse; Make the designer can quickly find reuse module; And to provide a complete global analysis ability.
He said, using the ExpeditionEnterprise design reuse, variant design process management, constraint management and library management, and other technology, can improve design efficiency by reuse.
