PCB Classification

“Pattern and Drill Specification” are used shorthandly to measure the manufacturability of the PCB: this generate a classification which is related to the PCBoard’s Services. Any way these classes generally permit to control the price of the PCB on demand service.

Parameter of these specification are:
- the minimum width for copper tracks (conductors) and gap (isolation) between them both for Outer and Inner layers;
- the minimum gap (distance) between cu-plated trough hole and lay out copper both for Outer and Inner layers;
- the minimum copper rings (difference between copper pad and hole sizes) both on outer and inner layers;
- the holes characteristic (minimum size and related production process);
- the required or needed hole accuracy (location and align registration);
- the solder mask characteristic (size of clearance related to copper lay out, minimum line size, devolpment in holes)
- mechanical requirements

Small or large values ​​of these characteristics determine the class of PCB technology, production, or its complexity.
For details on said class values​​, reference is made to the relevant tables.


Class A
Class B
Class C
Class D