Gold Plating Thickness Specification for PCB Contacts Gold is used on circuit boards for two reasons: it does not oxidise, and it survives repeated mating. Both properties depend on how thick the gold is and on what lies beneath it, and the gold plating thickness that suits a low cost…

Shunt Resistor Packages: Power and Thermal Limits A shunt resistor is the component that turns current into a voltage a circuit can measure, and it is chosen on the assumption that it will stay at the value printed on the reel. That assumption holds only if the part stays cool…

PCB Sample Order Pricing: What a Small Order Really Costs A sample order is the smallest useful unit of a board programme. It proves the fabrication process, the fit and often the function, and its price is dominated by fixed charges rather than by the boards themselves. Understanding that structure…

Conformal Coating Application and Masking Methods Guide A conformal coating is a thin polymer film that protects a finished assembly from moisture, dust, salt, and the small conductive debris that accumulates in service. It adds almost no weight and very little cost, yet it is often the difference between a…

Common Mode Choke: Preparation, Placement and Process Control A common mode choke is placed on a power input to block common mode noise, and at low frequency it does exactly that: the specified inductance is large and the impedance it presents to common mode current matches the datasheet curve. At…

Laser Direct Imaging: Preparation, Placement and Process Control Imaging is where a circuit pattern is transferred from data into photoresist, and for decades that meant a film and a lamp. Laser direct imaging replaces the film with a scanned beam, removing a whole class of distortion problems and making fine-line…

Pin-In-Paste: Preparation, Placement and Process Control Through-hole connectors are mechanically robust and electrically reliable, and they are also the reason many assemblies need a second, slower soldering process. Pin-in-paste, sometimes called intrusive reflow, removes that step by printing enough solder paste into and around the holes so that the joints…

Quasi-Peak Detector: Preparation, Placement and Process Control A pre-scan with a peak detector shows a point above the limit line, and the conclusion that the product has failed follows immediately. It is often the wrong conclusion. The peak detector is a fast and deliberately conservative screening tool, and the formal…

Aluminum Pcb Cost: Preparation, Placement and Process Control An aluminum board exists to move heat, and every cost decision on it follows from that purpose. The metal core is the heatsink, the dielectric layer is the thermal interface and the copper is the circuit, and the three have to be…

Salt Spray: Design Rules and Process Limits Coastal installations, vehicle underbody modules, and outdoor equipment all expose electronics to chloride, and chloride attacks metal faster than almost anything else. A salt spray test reproduces that exposure in a chamber and compresses months of service into days. The test is easy…