PCB Yield Data Analysis: Reading the Numbers 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 yield data analysis gives you a practical advantage when you…

PCB Inspection Lighting: Seeing the Joint Properly 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 explains PCB…

Bare Board Shelf Life and Storage Control A bare board is not inert while it waits to be assembled. The copper oxidises, the finish changes, the laminate absorbs moisture and the mask cures further. The shelf life of a board is the time over which those changes stay inside the…

Tin Whisker Risk In Lead Free Assembly A tin whisker is a single crystal of tin that grows out of a plated surface over a period of months or years. It can be a few micrometres in diameter and long enough to bridge a gap between two conductors that were…

Moisture Sensitivity Level And Popcorning In Assembly A plastic packaged component absorbs water from the air, and the amount it absorbs depends on the material, the thickness of the body and the humidity it has been exposed to. When the part is heated rapidly in a reflow oven, that water…

Component Derating for Temperature and Voltage Margin Derating is the deliberate use of a component below its rated limit so that it has margin. It costs money and board area, and it is the cheapest reliability measure available when it is applied to the parts that actually limit the life…

Selective Soldering for Mixed Technology Assemblies Most modern boards are a mixture. A densely packed surface mount area sits on one side, and a handful of connectors, transformers or power devices are still pushed through holes on the other. Sending that board across a wave solder machine would reflow the…

Can Seamer Control Board Design for Industrial Use A can seamer is an industrial machine that closes a lid onto a filled container with a pair of rotating rollers, and its control board has to coordinate several motors, read a set of position sensors and stop instantly when a guard…

Portable Fan Circuit Design: Motor, Battery and Noise A portable fan is a battery, a small brushless motor and a charging input in a housing that the user holds. The electronics are simple, and almost every design decision is about noise, run time and cost. What the Product Does The…

Second Side Reflow and Component Retention Methods When a board has components on both sides, the second pass through the oven heats parts that are already attached and upside down. Some of them stay in place because the molten solder holds them, and some do not. Understanding which category a…