Immersion Silver or Hard Gold: Which Surface Finish Fits Surface finish is chosen twice in the life of most products: once when the board is assembled, and again every time a connector is mated. Immersion silver and hard gold sit at opposite ends of that spectrum. One is a thin,…

PCB Drill Targets: Registration, Tooling and Hole Accuracy Drilling looks straightforward until the numbers are measured. A hole is supposed to land in the centre of a pad, but between the artwork used to define the pad and the drill that finally makes the hole there are lamination, bake cycles,…

10-Layer Buried Via PCB: Cost Drivers and Quote Levels A ten layer board is expensive on its own. Add buried vias and the price can double, because buried vias require the board to be built in stages, with inner layer pairs laminated, drilled and plated before the outer layers are…

EV PCB Manufacturing Cost: Materials, Layers and Supply An electric vehicle contains more electronics than most people expect, and almost none of it runs on a comfortable 12 volt rail. Battery management, traction inverters, on board chargers and DC/DC converters all work at high voltage and high current in an…

Preventing Board Warpage Through Reflow A board that goes into a reflow oven flat and comes out bowed has not been damaged by a single event. It has been deformed by a temperature gradient, and the deformation has persisted because the material lost its stiffness while it was hot. Preventing…

PCB Filter Circuit Design: Layout, Types and EMI Filtering A filter circuit is the part of a design that decides which frequencies are allowed to travel and which are turned away. On a board it appears in many forms, from a capacitor beside a power pin to a multi element…

PCB Differential Signaling: Impedance and Length Matching Differential signaling sends one signal down two traces instead of one and recovers the data from the voltage between them rather than from the voltage to ground. That one change buys immunity to a large class of interference, but it also imposes rules…

PCBA Capability: How to Judge a Manufacturer Process Two assembly houses can quote the same board within a few percent of each other and deliver very different products, because the quotation says nothing about the capability behind it. PCBA capability is measurable, though: it shows up in the smallest package…

PCB Plating Cost: Copper, Nickel and Gold Per Area Plating is one of the few PCB processes where the raw material price is set by a global commodity market, and that makes it unusually sensitive to thickness, area and the metal involved. A board that needs a gold edge connector…

FPGA Design Flow from Entry to Configuration An FPGA design is built in stages that run in a fixed order, and each stage exists because the one before it cannot answer the question the next one asks. Code can be simulated but not placed; a netlist can be placed but…