It is highly recommended to use functional test fixtures to test every board that comes off the production line to minimize defects and avoid defective products reaching customers. Despite these efforts, final testing of assembled PCBs is crucial as it serves as the ultimate evaluation of both the product and the process. This final testing may involve both dynamic methods and automation systems, often used in combination. "Manual" testing relies on visual inspections by operators using optical instruments, while automation systems use computer-aided graphics analysis to detect defects. An automation system may include all methods except for manual light detection.
IBM's transformation from a hardware manufacturer to a service-based IT and business solutions provider exemplifies this shift. In 2006, IBM's hardware revenue accounted for just 24.61% of its total income, with the remainder coming from global services, software, and financial services. The integrated circuit (IC) industry similarly reflects this trend, as value creation moves from manufacturing to design, development, and lifecycle management services. Driven by globalization, technological innovation, and market demands, the IC industry is transitioning from a production-centric model to one focused on delivering comprehensive system solutions and value-added services. This shift is particularly visible in the global PCB and Chinese electronics markets, where manufacturing and services increasingly converge.
Additionally, component placement should minimize unnecessary rotations and movements during assembly, avoid placing components on both sides of the PCB to reduce labor costs, and ensure even distribution to prevent warping and heat concentration. The use of oval pads, strategic positioning holes, and careful layout planning can help avoid manufacturing defects such as tin bridges and component damage. In practice, good design should also consider measures to reduce electromagnetic interference and improve manufacturability.
The process of soldering Surface Mount Devices (SMDs) involves several steps: applying a solder bead to the PCB pad, positioning the SMD on the pad, heating and securing it with a soldering iron, and inspecting the solder joint to ensure proper attachment. Liquid flux is applied to both ends of the SMD, and additional soldering is performed to secure the component to the PCB pad. After soldering, the joint is checked for secure attachment, and excess solder can be removed with a solder wick. This approach allows for hands-on assembly, reducing costs associated with professional prototyping.
During PCB processing, various methods are used to clean circuit boards, primarily to remove residual flux and rosin after soldering. Water washing, combined with industrial detergent, is the main method. After washing, PCBs typically require baking if they are in the final processing stages. Three types of washing solvents are commonly used: 1、Chlorinated solvent wash water: A mixture of chlorinated solvents that effectively dissolves rosin flux and evaporates without leaving residues. 2、Hydrocarbon solvent wash water: Utilizes hydrocarbon cleaning agents, available in quick-dry and slow-dry types, suitable for high-precision PCB cleaning due to their non-toxic and environmentally friendly properties. 3、Water-based plate washing water: An eco-friendly and non-toxic option; however, caution is needed due to its potential to cause corrosion on metal components if not adequately protected.
The report forecasts a return to modest growth for North American PCB production by the end of 2016, with growth expected to continue through 2018. This growth trend also applies globally, including key PCB production regions such as China, Taiwan, Korea, and Japan. The study presents data and analysis on various aspects of the PCB market, such as market size, sales growth, product types, vertical markets, revenue trends, layer counts, material trends, labor and R&D spending, revenue per employee, and U.S. import/export activities. A special feature includes forecasts by Dr. Hayao Nakahara, a prominent industry analyst, on total PCB production in the Americas and worldwide through 2018.