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64 SMT Magazine • March 2016 neering begins the new product introduction. On PCBAs, the team works to optimize designs with SMT layouts that minimize labor cost. However, the product development team also looks at product lifecycle management (PLM) issues, plus design for procurement. Factors such as component commonality with the cus- tomer's existing products, availability, supplier quality and price are considered in bill of mate- rial (BOM) and approved vendor list (AVL) de- velopment. Finally, agency pre-approval testing is also supported to ensure that the final design is manufacturable, cost competitive and com- pliant with regulatory issues. The benefit of this integrated approach be- comes even more obvious when a PCBA project that is in not manufacturable is awarded. For example, an OEM who had worked with an EMS provider with limited design capability awarded a project which included a PCBA that had been modified to pass agency testing with kapton tape, jumper wires and through-hole compo- nents with uniquely formed leads. In a tradi- tional EMS-only model, there would be limits to the redesign support available. In this case, the manufacturing team did not feel the PCBA could be manufactured in volume efficiently or with consistent quality, however the engineer- ing team was able to redesign the PCBA to be both manufacturable and pass agency testing. DFT is another area where a combined de- sign and EMS model can enhance support op- tions. In the traditional EMS model, DFT exper- tise focuses primarily on design enhancement to improve accessibility and test coverage. Test program development and fixture design are also commonly available. In the integrated de- sign and EMS approach services may expand to functional tester design or a standardized test platform approach. This broadens the range of lower cost test options, as modifying a standard platform for multiple customers can reduce non- recurring engineering costs. This can be par- ticularly important to OEMs with low volume products, legacy products and highly regulated products. For example, when customers don't have strong test expertise in-house, this contrac- tor's engineering team can help with both DFT recommendations and development of custom functional testers. Test fixture design and fabri- cation is also supported. The engineering team takes custom requirements and designs rack- based test systems with mechanical interfaces. Software is written using National Instruments' Labview. Capabilities include standard electron- ics and electro-mechanical devices. Systems can include use of optical interfaces or automated visual inspection with cameras. Typically, these custom functional test systems are best for low- to-medium volume production. In-line functional testers which include a clamshell box with safety systems to protect employees from high voltage have also been de- veloped. These systems typically use a National Instruments data acquisition card embedded in the test box with additional peripheral circuitry with varying voltages, relays and switches that interact with test points though pogo pins. These testers typically support medium volume in-line production. The ability to look at a wide range of test considerations during the product develop- ment process enables an engineering team to design in built-in tests such as JTAG or a fixture- less testing via a test through connector strat- egy. This flexibility can be important for dense PCBAs with limited space. This contractor uses in-circuit test systems in the design process to provide a report on coverage. Functionality is analyzed by circuit block. Where possible PCBAs are layout to facilitate a bottomside sur- face mount test probe, however, options for this are limited if the PCBA has high-speed circuitry or high-precision analog circuitry. To reduce the thE aPPEal of a CoMbInEd EngInEErIng and ManufaCturIng SolutIon