What is a Gerber File?

What is a Gerber File?

Gerber is a standard electronics industry file format used to link design information to manufacturing for many types of printed circuit boards. Gerber data is a digital format representing the copper pattern per layer.

Two standards exist, but it is advised to use the RS-274X file format where each layer information is in a unique file.

For each layer a Gerber file is required. For example for a 2 layer pcb we will require a Gerber file for:

• top silkscreen
• top soldermask
• top pastemask
• top copper
• bottom copper
• bottom soldermask
• bottom pastemask
• bottom silkscreen
• board outline

Except of the Gerber files a lot more items have to be specified:

• the location of the holes, their diameter and if the holes are plated through hole (PTH) or non plated through hole (NPTH) and if they are blind or buried and in between which layers.
• The place of the holes is placed in an excellon drill file.
• the color of the silkscreen and solder mask, and possibly the type of solder mask
• the type of plating or finishing
• the copper thickness for each different layer and total board thickness
• the thickness and type of substrate or isolator for the different layers (2 last points are called the stackup)
• panelization: number of pcbs per panel, type of contour routing: v-cutting / v-scoring or break routing / tab routing, technical border
• fiducials
• peel off, chamfered holes, special marking, …

This information has to be specified in a description file like README.TXT

Other pcb description formats exist like ODB++, IPC-2511 (GenCAM), EDIF: Electronic Design Interchange Format, OpenAccess, JPCA-EB02 (Fujiko).

myProto is also able to accept pcb descriptions in ODB++.

For more information about any of the other types written above, please contact us.