ByNolan Johnson，CAD / EDA Manager，Sunstone电路
How efficient is your PCB manufacturing designer?
When a design team puts their first prototype onto the workbench for testing and verification, the team must simultaneously debug the following:
• The concepts in the schematic design
•布局的实施概念
• The behavior of any firmware/software onboard
•所选部件从组件数据表文档，功能规范和原理驱动模拟数据的预期相互作用的能力
•制造商制造布局指示它们构建的能力的能力
That’s a lot to debug, all at the same time. The more a manufacturing provider can shorten this list for the design team, the better. The more the board fabricators can remove debugging discussions that start with “I found a short in the board you built me,” the more the board manufacturer can help the design team target functional behaviors, instead of build errors; resulting in a shortening of the product design cycle.
Designing for durability also helps promote yield. photo: istockphoto
设计流是电子产品开发周期效率的关键贡献者。但是，一个需要更深入地意识到该过程的原型制造部分对于早期和有效地捕获设计误差至关重要。这是原型硬件，毕竟验证了CAD文件内容体现的原始设计意图。
Optimization for production
Close attention to design issues increases the overall manufacturing yield of the end product. Designing for durability also helps promote yield. It is a good idea to implement the same design ideas during prototyping, but with different target criteria. Here are key factors to strive for:
•生产设计优化producti体积on
•针对快速转弯优化的原型
•生产针对元件成本进行了优化
•Prototypes optimized for functional verification
•生产设计，减少制造成本
•缩小设计错误的原型
制造业质量对原型设计和小型投资回报（ROI）的恢复有所影响。印刷电路板（PCB）制造过程可以极大地影响各个设计团队。
Manufacturing quality can be defined as:
•安排遵守（按时交货）
• Design adherence
• Accessibility
• Yield
These four factors affect the manufacturing quality of a prototype PCB project.
1. Schedule adherence
Delivery schedule adherence (DSA) is used to calculate the timeliness of deliveries from suppliers. On-time delivery results in less expense to the customer’s design team. Occasionally, PCB’s are manufactured to a schedule; yet, the carrier causes delays outside the scope of both the manufacturer and the customer. In an effort to avoid delivery conflicts, a shortened prototype design phase overall, and a more cost-effective development project should be considered in the product development cycle.
2.设计遵守
Design adherence is the ability of the manufacturer to build exactly the board that the designer created. There are factors that can prevent design adherence such as, tolerances, machine processes, materials, and so on. Strict adherence is not always possible in the real world.
It is important to identify design adherence issues. Violations in design adherence can be debugged back to unintentional problems, opens or shorts in the PCB itself, or caused by manufacturing issues. These problems could be caused by components that do not perform exactly as specified in the data sheet; such as a flaw in the circuit design itself.
Design Adherence is the ability of the manufacturer to build exactly the board that the designer created. photo:sunstone circuits
一个例子是2006年摩托罗拉·拉兹尔手机。设备发布前两天，一些精明的手机销售代表注意到工厂翻新的设备库存异常高。由于razr甚至没有出售，但这些工厂翻新的设备无法来自客户退货。相反，这些可能重新制作了工厂最终QC的设备。结论认为，在工厂的这种高故障率将转化为现场的高损失手机，这些精明的销售代表建议客户暂停购买该特定电话。代表担心客户回报的潜在冲击，以及处理每次回流/交换的费用。2006年初，面临着高速的客户回报率，一些细胞运输公司完全停止了razr的销售。问题最终被追溯到错误的组件，并在生产设施中解决。
The type of issue experienced by the Razr in 2006, cannot always be caught in prototype, but some issues can be caught. In the prototype phase, design adherence helps the design team concentrate on the behavior of the design during debugging, not on whether the PCB manufacturer built what the design team specified.
Another example is based on a standard return merchandise authorization (RMA) rate of about 2% for PCB manufacture and costs of $1,000/day in design team costs for each day of delay. A firm generating 1,000 orders per day of prototype boards, should expect to generate about 20 customer rebuilds daily. If the RMA rebuild requires 3 days to get to the customer, then design teams lose $60,000, cumulatively, per day to manufacturing RMA. An RMA rate of less than 1% would translate to an RMA-related loss one-third of the baseline established. Such an RMA rate annualizes to almost $10 million dollars of saved customer R&D budget.
Just as the Razr example demonstrates that one can rate a product’s quality in part by examining the RMA rates, one can also get a feel for a prototype PCB manufacturing partner from their RMA rates. To do so, a manufacturer’s ability to transform CAD files into a prototype (Quick-turn manufacturing process) with a low level of RMA work shows that a manufacturer brings extra value by: 1) clearly and proactively publishing its Quick-turn manufacturing criteria; 2) providing tools and utilities that design teams can use to incorporate the Quick-turn criteria from design start; 3) ensuring said manufacturer complies with all customer-supplied production manufacturing instructions; and, 4) offering design reviews by request.
3. Accessibility
The role of a prototype-manufacturing partner is a collaborative one and accessibility is critical in the product development cycle. It is important to your overall productivity that your schedule and terms can be met. With current global business practices, the design team may be on a very different time schedule from the manufacturing facility. Although, it might be tolerable to work with 16 hour time differences to the production facility, the prototype manufacturing provider needs to be much more accessible than the production facility. If your PCB partner isn’t available for technical assistance during unconventional times, the design team may be delayed until the next day on a key piece of technical information.
4. Yield
As previously mentioned, production yield levels are a key leading indicator for ongoing service levels during a product’s lifecycle. Though yield becomes critically important for production, it is still of importance through the prototyping process.
当设计团队使用原型制造合作伙伴时，在与客户共同努力，以确保准确，高效，快速满足原型板的订单，那么设计团队的福利：
• Reducing the number of debug factors to contend with on the test bench
• Maximizing progress per design spin
• Reducing the overall number of design spins required
• Maintaining development schedule due to a lack of delays from the PCB fabricated process
• Increasing attention to the manufacturability of the design, both in the design team and at the PCB manufacturing facility
•越来越多的赔率，可靠的制造生产设计将提高产品的盈利能力，降低支持产品的长期服务成本
所有这些利益通过减少浪费和减少由于制造延误而过度运行的预算来帮助行业获胜。项目逐步效率转化为大量的行业范围内的资源储蓄，并在设施的高效运营;因此，为设计团队而言，保持降低成本，并为每个产品的产品改进ROI。当然，具有更高性能，更高的价值和更高的边距开发的新产品意味着该产品成为公司MoneyMaker的更快。
提起：Design World articles
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