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　　怎样使用原型呢？原型只挑战部分系统设计吗？还在重复建造PCB原型来调整设计吗？EDN怎样覆盖PCB设计呢？

　　我花费了很多时间在与EOEM（新颖电子设备制造）市场公司的会面上。大多数那些见面是有这些公司的半导体销售商一起参加的。但最近在西北方的行程中，我在一些不同类公司上花费了时间，其中的两个属于PCB(印制板)原型领域。这样的会见使我思考工程师在设计过程中怎样使用PCB原型。我将提供一些我所听说过的事情。我也希望能在网上本文译文旁边的评论区域，得到读者的反馈，你可以告诉我和其他读者，你怎样使用PCB原型的。

　　首先，我会见了LPKF Laser & Electronics的相关人士。LPKF制造允许设计工程师快速建立自己原型PCB的设备。许多年以前，EDN在一篇技术文章中提到其有趣的特点：见"Prototyping tools transform design dreams into reality." LPKF提供连同制粉机和电镀系统在内的受计算机控制的PCB光绘仪。它基于所需的多层板和SMT（表面贴装技术）支持，虽然价钱不断升高，但只要花费最少$10,000
就可以购买到制造PCB原型的装置。公司甚至提供基于激光的小型产品光绘仪。

　　LPKF董事长Stephan Schmidt声称大多数公司购买设备，是由于在设计过程中建立原型的需要，是受设计工程师驱使的。Schmidt提出例如仿真的技术不是没有价值的。但他认为当设计人员做一系列原型来测试系统架构和设计时，经常会屈服于更高性能和更好表现的系统。

　　即使实验里不立即需要原型系统，也许仍需要LPKF目录的拷贝。在目录后部，公司提供PCB制造的技术指导。虽然目录呈现了与LPKF产品相关的消息，还有一些通用信息，包括微波与RF系统设计和SMT设计的部分。LPKF鼓励工程师教育的努力也值得赞扬。公司为高校工程师预科项目更新了装置。

　　我行程的后期，我会见了Sunstone Circuits，专攻PCB原型制造商。最初，Sunstone从事PCB生产行业，但几乎所有PCB生产行业都挪到了亚洲。Sunstone允许设计人员在线指定和订购PCB产品，通常在两天内送到。公司也提供免费的PCB设计软件。

　　我原本推测大部分订购PCB原型的设计人员不会定购目标系统PCB要素。我习惯于看参考设计和带额外提供芯片和测试模块通路连接的开发板。但是Sunstone说，80~90%的订单源于目标系统PCB要素。Sunstone的执行副主席和首席运营官Rocky Catt声称一些设计人员用比产品板更多的层来建立原型PCB。对原型而言，设计人员依靠自动布线设计也许会导致额外层，而对产品板，设计人员将板子最优化来达到层数最少。

　　怎样使用原型呢？原型只挑战部分系统设计吗？还在重复建造PCB圆型来调整设计吗？EDN怎样覆盖PCB设计呢？我们能传递你所需的信息吗？你当然能发e-mail或打电话给我要求回答，但通过在线发表评论，还有其他读者也能够从你的想法里获益。

　　英文原文：

　　PCB prototypes add value in the design process

　　How do you use prototypes? Do you prototype only challenging parts of a system design? Do you iteratively build prototype PCBs to tune a design? How should EDN cover PCB design?

　　By Maury Wright, Editorial Director -- EDN, 9/13/2007

　　I spend a good portion of my time meeting with companies in the EOEM (electronics-original-equipment-manufacturing) market, and most of those meetings are with semiconductor vendors due to the vast number of such companies. But on a recent trip to the Northwest, I spent time with some different types of companies—two of which are involved in the prototype-PCB (printed-circuit-board) area. The meetings got me thinking about how engineers use prototype PCBs in the design process. I’ll offer up a few things I heard. I’m also hoping that you will respond in the Feedback Loop comment section located alongside the online version of this article and tell us and your fellow readers how you use prototype PCBs.

First, I met with LPKF Laser & Electronics. LPKF makes equipment that allows design engineers to quickly make their own prototype PCBs. A number of years ago, EDN ran a feature on this technology that you might find interesting: See "Prototyping tools transform design dreams into reality." LPKF offers computer-controller PCB plotters along with milling machines and plating systems. For as little as $10,000, you can buy the gear you need to build PCB prototypes, although the price can escalate based on your needs for multilayer and SMT (surface-mount-technology) support. The company even offers laser-based plotters for small production runs.

　　LPKF President Stephan Schmidt claims that design engineers drive the purchase of most of the company’s systems due to the need for building prototypes during the design process. Schmidt doesn’t suggest that techniques such as simulation aren’t valuable. But he claims that designers often yield higher quality and better performing systems when they can do a series of prototypes to test the system architecture and design.

　　Even if you don’t have an immediate need for a prototyping system in your lab, you might still want to request a copy of the LPKF catalog. In the back of the catalog, the company offers a technical guide on PCB manufacturing. Although the catalog presents the information relative to LPKF products, there is also good general information, including sections on design for microwave and RF systems and on SMT designs. LPKF is also worthy of praise for its efforts to encourage engineering education. The company provides refurbished gear to high-school pre-engineering programs.

　　Later in my trip, I met with Sunstone Circuits, a manufacturer that specializes in prototype PCBs. Originally, Sunstone was in the production-PCB business, but almost all of the production-PCB business has moved to Asia. Sunstone allows designers to specify and order PCBs online and often can deliver products in two days. The company also offers free PCB-design software.

　　I would have guessed that most designers ordering prototype PCBs would not order the PCB in the target-system form factor. I’m accustomed to seeing reference desig
ns and development boards with extra connections that offer access to interconnects between chips and to test ports. But Sunstone claims that 80 to 90% of its orders are in the target-system form factor. Rocky Catt, Sunstone’s executive vice president and chief operating officer, claims that some designers will build prototype PCBs with more layers than the production board will use. For the prototype, the designer might rely on an autorouted layout that could lead to extra layers, whereas for the production board, the designer will hand-optimize the board to minimize the number of layers.

　　How do you use prototypes? Do you prototype only challenging parts of a system design? Do you iteratively build prototype PCBs to tune a design? How should EDN cover PCB design? Are we delivering information you need? You can certainly e-mail me or call me with answers, but by posting your comments online, your fellow readers can benefit from your thoughts as well.