Solder Mask Sliver: Preparation, Placement and Process Control Solder mask is a coating, not a structural material. Where it has to sit between two closely spaced pads or between a pad and a trace, it forms a narrow strip that has to survive printing, placement, reflow and often cleaning. If…

Prototype Order: PCB Prototype Checklist Before the Order Is Placed A prototype order is small, quick and usually urgent, which is exactly why the details are skipped and the boards come back wrong. Working through a short checklist before the data is released costs minutes and prevents a second cycle.…

RF Power Amplifier Layout Guide An RF power amplifier converts direct current into radio frequency power, and the layout decides how much of that power reaches the antenna and how much becomes heat. Every millimetre of the ground return and every nanohenry in the matching network changes the result. What…

Solder Pot Maintenance and Wave Quality The solder in a wave machine is a working alloy, and it changes with use. Copper, gold, nickel and iron dissolve into it from the boards and the components that pass through, the tin oxidises at the surface, and the flux chemistry leaves organic…

Test Point Design And Coverage For In Circuit Test A test point is the surface where a spring loaded probe touches the board, and it is the only interface between the product and an in circuit tester. Its size, its spacing, and its position decide whether a fixture can be…

Salt Spray Testing and Corrosion Resistance of PCB Finishes A salt spray chamber is one of the oldest tools in corrosion testing, and it remains one of the most requested by customers. It produces a repeatable, visually striking result in a short time, which makes it attractive for specification. It…

PCB Fabrication Cycle Time and How Quick Turns Work A standard double sided board takes about a day of machine time to build, yet the advertised delivery is often much shorter. Understanding the cycle time of each step explains what a quick turn can achieve and where the compression has…

PCB Antenna Keepout Design Guide An antenna printed on a circuit board is sensitive to everything placed near it, and the keepout is the space that has to be left empty. A design that ignores it produces a radio that works on the bench and fails in the enclosure, with…

Small Volume SMT Assembly from Quotation to Shipment A development team that has finished a design needs boards assembled in tens or hundreds rather than thousands. Small volume smt work is organised differently from mass production, and knowing the sequence removes most of the delay from a first order. What…

Humidity Testing and Damp Heat for Electronic Assemblies Water is the most common cause of long term electronic failure, and it rarely arrives as an obvious splash. A thin adsorbed film, a slow condensation cycle, or a residue that becomes conductive when the air turns humid are all enough to…