Moisture Bake and Popcorn Prevention for PCB Assembly Plastic packages absorb water from the air, and that water turns to steam the moment the package reaches reflow temperature. The result is a package that splits from the inside, a bond wire that lifts, or a crack that never shows on…

Component Obsolescence Management for PCB Assembly Components disappear. A part that was available in volume last year can be allocated, last time buy or obsolete this year, and the way a product is designed decides how much that costs when it happens. Obsolescence is predictable in principle and ignored in…

Component Solderability and Shelf Life Control in Assembly A component that was perfectly solderable when it was packed does not stay that way forever. Terminations oxidise, intermetallic layers grow, plating corrodes and the flux that was designed to remove a thin oxide stops being able to cope. Solderability is a…

Via Filling and Plugging: Tenting, Fill and Planarisation A via does not have to be open. It can be covered, plugged or completely filled, and the choice is decided by what sits above the via and by what the via has to survive. The words are often used interchangeably, and…

Measling, Weave Exposure and Laminate Cosmetic Defects Open a batch of boards and everything works, yet the surface looks wrong: pale crosshatched patches, faint fabric texture, or whitish spots that appear only after soldering. These are laminate cosmetic defects, and they generate more arguments between fabricators and customers than almost…

High Purity Copper Foil In PCB Fabrication Copper foil is the layer that becomes every conductor on a board, and its properties are usually taken for granted until a fine line etch or a high frequency measurement exposes them. Two foils of the same nominal thickness can behave differently because…

Land Pattern Design: Pads, Fillets and Density Levels The land pattern is the copper the component sits on. It decides how much solder forms the joint, how much the component can move, and how much of the joint an inspector can see. It is defined once and then inherited by…

PCB Acrylic Coating: A Simple Protective Film Buyers and engineers often focus on the finished product and forget the production line behind it. In practice, most field failures can be traced back to process decisions made during assembly. Understanding PCB acrylic coating gives you a practical advantage when you choose…

PCB Coating Cure Check: Proving It Is Dry Buyers and engineers often focus on the finished product and forget the production line behind it. In practice, most field failures can be traced back to process decisions made during assembly. Understanding PCB coating cure check gives you a practical advantage when…

Wireless Charging Circuit Design for 15 W Systems Inductive charging at fifteen watts is a mature technology with a well defined architecture, and the design effort goes into the details: the coil, the resonant network, the control loop and the thermal path, not into the principle. How Inductive Charging Works…