High-Frequency PCB Materials and Hybrid Stackups A high-frequency PCB is usually described by its material rather than by its geometry, and that emphasis is correct. Once a signal spends a meaningful part of its energy in the laminate instead of the copper, the loss tangent of the dielectric, not the…

Ceramic Substrate Manufacturing: Dry Pressing, Tape Casting and Metallization Ceramic substrates solve a problem that no polymer laminate can solve: they conduct heat well, hold their dimensions at temperatures that would destroy FR4, and stay electrically insulating while doing it. The trade is that they cannot be made with the…

PCB Design Mistakes That Stop a Prototype at CAM When a prototype comes back late, the cause is usually not the fabricator. It is the data. A layout that passes every check inside the CAD tool can still stop at CAM, because the checks in the tool model the schematic…

COB LED vs SMD LED: Chip-on-Board Packaging and Thermal Design Two LED products can emit the same number of lumens and still behave nothing alike on a board. A COB LED bonds many dies directly to the substrate, while an SMD LED packages each die in its own housing and…

Switching Regulator PCB Layout: Loops, Grounding and Checks A switching regulator is a small circuit with a large appetite for current, and the layout decides whether that current stays where it was planned or sprays across the board. The electrical design can be textbook correct and the prototype still fail,…

FPC ENIG Surface Finish: Electroless Nickel Immersion Gold in SMT Soldering Flexible circuits rarely fail because the copper itself gives up. They fail at the interface, where a thin stack of nickel and gold has to survive reflow, repeated bending and years of thermal cycling. FPC ENIG, the finish most…

Multilayer PCB Manufacturing Challenges: Registration, Lamination and Drilling A ten layer board is not simply a four layer board with more copper. Every layer added multiplies the number of interfaces that can move relative to one another, and it lengthens the process chain that each panel must survive. Multilayer PCB…

PCB QFN Rework: Removing a Part With No Leads: Design and Assembly Considerations Modern electronics depend on boards that are assembled correctly the first time. Every product – a phone, a charger, a medical instrument or an industrial controller – relies on thousands of solder joints that must conduct current…

PCB Hand Soldering Temperature: Process Details and Inspection Points Modern electronics depend on boards that are assembled correctly the first time. Every product – a phone, a charger, a medical instrument or an industrial controller – relies on thousands of solder joints that must conduct current for years. This article…

PCB Soldering Iron Tip Selection: A Practical Review for Manufacturing Teams Electronics manufacturing has become a discipline of small details. Solder paste volumes, placement accuracy, temperature profiles and inspection limits all add up to the final result. This guide looks at PCB soldering iron tip selection from the perspective of…