Coil Circuit Board

A planar-coil PCB where the inductive winding is etched directly into copper rather than wound from wire. The hallmark traits are an etched-trace coil pattern in place of conventional copper-wire turns, equal line width and line spacing across the spiral for predictable AC impedance, and tightly controlled board flatness for repeatable mutual inductance with mating coils or sensor targets. Test coverage requires more than standard flying probe — open and short detection for tight-pitch coils calls for inductance measurement, and dielectric strength of solder mask and inter-trace ink layers must be verified for the operating voltage. Used in inductive components for measurement and control: position sensors, proximity sensors, current transducers, wireless power coils, and rotary encoders where geometric repeatability beats hand-wound parts.