PCB Drill File may refer:
PCB NC formats: A collection of widely used drill file formats in PCB production.
PCB NC drill files convey PCB drilling and routing information. The NC formats were originally designed by CNC drill and route machine vendors as proprietary input formats for their equipment, and are known under their company name: Excellon, Hitachi, Sieb & Meyer, Posalux, etc. These formats are similar as they are based on RS-274-C and related to G-code. In 1985 IPC published a generic standard NC format, IPC-NC-349. Later XNC was designed, a simple strict subset of IPC-NC-349, designed not for driving machines but for exchanging drill information between CAD and CAM. They are collectively referred to as (PCB) NC files.
The NC files are primarily used to drive CNC machines, and they are adequate for that task.
They are also used to exchange design information between CAD and CAM, for which they are not adequate: essential information such as plating and drill span is missing. Furthermore, the NC output in CAD systems is often poorly implemented, resulting in poor registration between drill holes and copper layers and other problems. To exchange data between CAD and CAM it is more preferred to use the Gerber format. The quality of the Gerber file output software is typically good, and Gerber supports attributes to transfer meta-information such as plating and span.
Gerber file format: the de facto standard of data transfer from design to fabrication, and which can transfer drill information.
The Gerber format is an open ASCII vector format for printed circuit board (PCB) designs. It is the de facto standard used by PCB industry software to describe the printed circuit board images: copper layers, solder mask, legend, drill data, etc.
The official website contains the specification, test files, notes and the Reference Gerber Viewer to support users and especially developers of Gerber software.
Gerber is used in PCB fabrication data. PCBs are designed on a specialized electronic design automation (EDA) or a computer-aided design (CAD) system. The CAD systems output PCB fabrication data to allow fabrication of the board. This data typically contains a Gerber file for each image layer (copper layers, solder mask, legend or silkscreen…). Gerber is also the standard image input format for all bare board fabrication equipment needing image data, such as photoplotters, legend printers, direct imagers or automated optical inspection (AOI) machines and for viewing reference images in different departments. For assembly the fabrication data contains the solder paste layers and the central locations of components to create the stencil and place and bond the components.
There are two major generations of Gerber format:
- Extended Gerber, or RS-274X. This is the current Gerber format. In 2014, the graphics format was extended with the option to add meta-information to the graphics objects. Files with attributes are called X2 files; those without attributes are X1 files.
- Standard Gerber, or RS-274-D. This obsolete format was revoked.
The standard file extension is .GBR or .gbr though other extensions are also used.