PCB Sampling in Receiving: Key Process and Quality Checks 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 Supplier Corrective Follow Up: Key Process and Quality Checks 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…

Copper Balance and Panel Distortion Control in Lamination A multilayer board is a stack of materials with different expansion and shrinkage behaviour, pressed together under heat and pressure. If the copper distribution is uneven, the layers move by different amounts and the panel comes out of the press wanting to…

PCB Supplier Performance Data: What Buyers and Engineers Should Check 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 supplier performance data from the perspective of a PCBA…

Solder Wetting And Dewetting Defects Wetting is the process by which molten solder spreads across a metal surface and forms a continuous metallic bond at the interface. It is not simply solder sitting on a pad. A properly wetted joint shows a small contact angle, a smooth concave fillet that…

Capacitive Sensing Electrode Design A capacitive control panel measures the change in capacitance produced by a finger near an electrode. The change is a fraction of a picofarad against a background of several picofarads, so the electrode geometry, the routing and the surrounding ground all matter as much as the…

Color Sensor Interface Circuit Design A color sensor measures the intensity of light in a few wavelength bands and reports the result as numbers. Turning those numbers into a colour that matches what a person sees requires an understanding of the light source, the filtering and the way the readings…

Connector Reliability Under Thermal Cycling A connector is a mechanical assembly made of several materials, and it is mounted to a board that expands at a different rate. The joints at its ends carry the resulting load, and they are the first to fail. Where the Stress Comes From The…

RoHS: Material Compliance Documentation for Assemblies Every product sold into a regulated market carries a documentation obligation. The materials have to be declared, the exemptions recorded and the evidence kept, and none of it is visible on the board. What Has to Be Declared The restricted substance requirements set limits…

Segment LCD Driver Circuit Design A segment liquid crystal display is one of the most durable and readable ways to show a few digits, and it works by chemistry rather than by light emission. The driver has to present the right waveform to each segment, and a direct current across…