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Introduction

Gerber X3

Gerber X2plus

Gerber X2

Gerber X

Gerber

The History of Gerber


See also:
10 Rules for Better Data

INPUT DATA REQUIREMENTS

Gerber X2plus officially released in April 2018 is the de facto format for transferring data from CAD to CAM, replacing Gerber X2.

X2plus includes the Gerber Job file, this file allows the designers to transfer important information that before had to be transferred as a separate and manually created document.

It is in a simple human readable format that can be extended by adding custom information.

The Job file does not include any commercial conditions such as price, quantity, delivery etc as these are order and supplier specific.

The Job file is a separate non-image file that contains the PCB characteristics as below:

  • Header – Information about the file itself, such as its creation date.
  • General Specs – Overall board characteristics such as finish.
  • Material Stack up – Specification of the stack up and characteristics of the materials used.
  • Design Rules – Rules used when laying out the PCB.
  • Files Attributes – Polarity and function (e.g. top copper layer) of all Gerber files.

X2 Layers

Header

Identifies the software generating the job file and may also include the file creation data and any necessary comments.

General Specs

Contains characteristics that apply to the whole board, such as:

  • Board Name & Revision
  • Size (X & Y), Size Tolerance (+/-)
  • Board Thickness
  • IPC-2221 Type (Single, Double, Multilayer, Blind Via etc.
  • Manufacturing Standard (IPC, MIL, JSS etc.)
  • Impedance Control
  • Required Logos
  • Via Protection Type (none, Tented, Filled etc)
  • Finish
  • Edge Plating

And so much more…….

Material Stack up

The material stack up defines the material attributes for each layer.

For example (not the actual format):

Layer Type: Legend – Colour: “White”
Layer Type: Soldermask – Thickness: 0.025 – Colour: Green
Layer Type: Copper – Thickness: 0.03556
Layer Type: Dielectric – Thickness: 0.34
Layer Type: Copper – Thickness: 0.01500
Layer Type: Dielectric – Thickness: 0.34
Layer Type: Copper – Thickness: 0.03556
Layer Type: Soldermask – Thickness: 0.025 – Colour: Green
Layer Type: Legend – Colour: “White”

Design Rules

The Design Rules contain the intended rules used by CAD to layout the copper layers.

This information is extremely useful for purpose of quotation and planning. It may also be used during the data analysis by the manufacturer to identify possible layout issues.

File Attributes

File Attributes contain the meta-information about the Gerber files in the fabrication data set.

The following Attributes are supported:

  • File Function (Legend, Copper, Soldermask etc)
  • File Polarity (Positive or Negative)
  • File Format (Gerber, NC, IPC356 etc)

Example of a Basic Job File

{
“Header”: {
“GenerationSoftware”: {
“Vendor”: “Ucamco”,
“Application”: “UcamX”,
“Version”: “2017.12”
},
“CreationDate”: “2018-01-20T15:59:51+01:00”,
“Comment”: “Example”
},
“GeneralSpecs”: {
“Part”: “Single”,
“Owner”: “Galactic Corporation”,
“ProjectId”: {
“Name”: “HFDF Controller nRF52832”,
“GUID”: “f81d4fae-7dec-11d0-a765-00a0c91e6bf6”,
“Revision”: “Rev. 2b”
},
“Size”: {
“X”: 160.0,
“Y”: 50.8
},
“LayerNumber”: 4,
“BoardThickness”: 1.6,
“ROHS”: true,
“IPC-600-Class”: 2,
“Finish”: “Immersion gold (ENIG)”
},
“MaterialStackup”: [
{ “Type”: “Legend”, “Color”: “White” },
{ “Type”: “SolderMask”, “Color”: “Green” },
{ “Type”: “Copper”, “Thickness”: 0.03556 },
{ “Type”: “Dielectric” },
{ “Type”: “Copper”, “Thickness”: 0.01500 },
{ “Type”: “Dielectric” },
{ “Type”: “Copper”, “Thickness”: 0.01500 },
{ “Type”: “Dielectric” },
{ “Type”: “Copper”, “Thickness”: 0.03556 },
{ “Type”: “SolderMask”, “Color”: “Green” }
]
}