The same factors that force electronics manufacturers to do more functional test also conspire to make functional test harder to do. Smaller, more complex products make the critical task of functional test all the more challenging.
Increasing mixed-signal content and decreasing nodal access shift more of the fault-detection burden to the functional test stations. At the same time, products must meet rising customer expectations for quality. And companies must deal with increasingly stringent regulatory and documentation requirements.
Despite increasing yields resulting from improved manufacturing processes and in-process test steps, such as in-circuit test, the need for functional test continues to grow. One indication of this trend is the projected growth of VXI instrumentation revenue shown in Figure 1.
As the technical demands of functional test grow, so, too, do the pressures of the business world. Increasing competition leads to tighter schedules for designers and test engineers, shrinking test budgets and overburdened engineering staffs.
These business pressures and the intense technical demands of functional test have put the spotlight on the functional test system procurement process. And because functional test is still a necessity, manufacturers must become more creative–more efficient and clever–in inventing or acquiring their functional test systems.
To work smarter and more effectively, manufacturers are gathering all the information possible about their operations. One area where they are seeking more detail is internal costs, including the real costs of functional test (Figure 2). They are also becoming more introspective, looking critically at their strengths and weaknesses. Armed with these new insights, they are making difficult choices based on what they perceive to be their core competencies.
This internal scrutiny leads either to focused efforts to improve existing processes or to a recognition that new approaches might be necessary. Either way, manufacturers are taking a hard look at their traditional custom test-system acquisition methods in an effort to cut costs and boost productivity.
To Make or To Buy?
Test departments had two traditional alternatives for procuring functional test systems. They could purchase components–including instruments, VXI mainframes, programming environments, computers and development software–and integrate them into a test system themselves. Or they could contract the development of the entire test system to an outside vendor, buying a turnkey system that required little or no customization by the in-house test department. Each of these methods has its benefits and drawbacks (Table 1).
Increasingly, manufacturers realized that a simple make-or-buy functional test decision didn’t reflect the complexity and breadth of their test needs. That realization led to a trend toward more diverse buying practices for functional test solutions. This diversification generally divides functional test customers into three categories:
o Some electronics manufacturers who have always developed their own functional test systems will continue to do so. They have decided that using their in-house expertise and keeping control of the system integration process outweighs any negatives that accompany building their own test systems.
o On the other end of the spectrum are manufacturers who prefer to procure complete functional test systems from an outside systems integrator. Companies choose this route either because they need short-term help when they reach the limits of their internal capacity or when internal test capability simply doesn’t exist.
o Somewhere in the middle is a new class of functional test customer. These manufacturers have evaluated the gains and sacrifices associated with the traditional make and buy options and have decided that their ideal solution combines the best of both. They seek an off-the-shelf platform that is somewhat prefabricated so their test engineers don’t have to start completely from scratch. Platforms of this type are flexible enough to allow customization so that the final version of the system is still targeted to their application.
Many electronics manufacturers choose a combination of these three methods in their operations because the acquisition method can be heavily influenced by the technical and business needs of the individual project. Manufacturers who strive for this project-level optimization are typically very concerned with the proliferation of noncompatible functional test stands and the inherent long-term support difficulties and inefficiencies that they bring.
What Can You Expect From Test Vendors?
In the face of this diversity, test-equipment vendors have been working on several fronts to make life easier for their customers, including those using traditional make and buy approaches and those seeking middle-ground solutions to their own test needs.
To simplify the process for manufacturers developing their test systems, vendors continue to improve industry standards and increase the selection of components that meet these standards. By working to strengthen standards, for example through the VXIplug&play Systems Alliance, test-equipment suppliers are making the task of multivendor system integration easier.
Vendors also have been working to simplify the test-system procurement process for electronics manufacturers who wish to buy their system from an outside supplier. By offering a wider range of services, users can choose a level of cooperation they feel comfortable with.
Vendors have added low-level racking and cabling, consulting and project-management services, and turnkey system design and implementation to their range of services to meet the needs of this group of users. These alternatives allow manufacturers to choose the amount of external expertise that best complements their in-house test-development talent. As more test vendors broaden their suite of such services, the risks and fears typically associated with sole-sourcing can be mitigated.
Vendors are also addressing the needs of the growing class of middle-ground users. Most of these users want to streamline system hardware development. Some are looking for prefabricated hardware platforms that can be customized for a variety of specific applications. Others are seeking industry-specific systems that can undergo minor adjustments to test a variety of components in industries such as telecommunications or automotive.
Regardless of the approach used for hardware integration, each system-development option has one thing in common: a significant software development effort (Figure 2). Recognizing this, some vendors now offer test-executive software to speed the overall system-integration task.
Competitive pressures and shrinking product life cycles are leading electronics manufacturers to scrutinize the effectiveness and efficiency of each segment of their operations. As a result, many right answers for functional test are beginning to emerge that don’t fall within the traditional choices of making or buying a functional test system. In each case, the right answer will depend on a company’s unique combination of core competencies, cost structures, test philosophies and business pressures.
Regardless of the approach they decide is best–developing their own system, buying a complete custom solution from an outside vendor, needing a solution somewhere in between these extremes or choosing any combination of these methods–functional test suppliers must match this new diversity of needs and buying preferences with equally diverse options in products and services. To do otherwise is to force-fit a less-than-optimal solution based solely on what a vendor has to sell, not on what solves the customer’s test and business challenges.
About the Authors
Jeff Stoltman is a Product Marketing Engineer at the Hewlett-Packard Manufacturing Test Division. He has 10 years of experience in the board-level ATE industry and holds a B.S.E.E. degree from the University of Wisconsin.
Chris DeSalvo, an 18-year veteran with Hewlett-Packard, is Sales Program Manager for the VXI Systems Division. He has held many technical marketing and management positions related to HP-IB and VXI instrumentation for functional-test applications. Mr. DeSalvo earned a B.S.E.E. degree at the University of Pittsburgh.
Hewlett-Packard Co., Manufacturing Test Division and VXI Systems Division, P.O. Box 301, Loveland, CO 80539-0301, (303) 679-3066.
Copyright 1995 Nelson Publishing Inc.