Copper

The copper statement defines geometry on a specified copper layer of the board stackup.

This statement can be used in the following contexts:

pcb-landpattern
geom statements in a pcb-module

Signature

  copper(<LAYER-INDEX>) = <Shape>

<LAYER-INDEX> - This expects a LayerIndex instance to select which copper layer to apply the created geometry.
<Shape> - The geometric Shape to create in this copper layer.

Usage

That are two contexts in which the copper statement can be used. In each context, the usage is slightly different.

In the pcb-landpattern context, the copper statement can be used standalone. This statement is used to create copper structures like an antenna in a landpattern. For example, see the ant-2GHz4-inverted-f-geom land pattern - here is an excerpt:

pcb-landpattern ant-2GHz4-inverted-f-geom :

  pad launch : smd-pad(0.5, 0.5) at loc(0.0, 0.25)
  pad gnd : smd-pad(0.9, 0.5) at loc(-2.1, 0.25)

  copper(LayerIndex(0)) = Line(0.5, [Point(-2.1, 5.15), Point(2.2, 5.15), Point(2.2, 2.51), 
                                Point(4.7, 2.51),  Point(4.7, 5.15), Point(6.9, 5.15), 
                                Point(6.9, 2.51),  Point(9.4, 2.51), Point(9.4, 5.15), 
                                Point(11.6, 5.15), Point(11.6, 0.96)])
  copper(LayerIndex(0)) = Line(0.5, [Point(0.0, 0.0),   Point(0.0, 5.15)])
  copper(LayerIndex(0)) = Rectangle(0.9, 5.4, loc(-2.1, 2.7))
  ...

This will generate a shape that looks like this:

copper_landpattern_example

In the following image the 2nd and 3rd copper statements are drawn in a different color to show their position in relation to the pads of this landpattern:

copper_landpattern_example_2

Geom/Module Context

In the pcb-module context, the copper statement can be used from within a geom statement. The geom statement provides the net to which this copper geometry will be assigned. The most common usage of this statement is defining ground planes or similar geometry with explicit shapes:

val board-shape = Rectangle(30.0, 40.0)

pcb-module top-level: 
  ...

  geom(GND):
    val sh = offset{_, -1.0} $ RoundedRectangle(30.0, 10.0, 3.0)
    copper(LayerIndex(0, Bottom)) = loc(0.0, -15.0) * sh

Notice the use of offset to shrink the RoundedRectangle shape by 1mm. The loc function is used to transform the shrunken shape into position in the lower half of the PCB.

Constructs a shape on the bottom layer with geometry like this:

copper_geom

Syntax

geom(my-net):
  copper(LayerIndex(0)) = Circle(0.0, 15.0, 1.0)
  copper(LayerIndex(1)) = Line(1.0, [Point(0.0, -5.0) Point(5.0, -5.0)])

Description

copper(LayerIndex(0)) = Circle(0.0, 15.0, 1.0) Create a copper circle at (x,y) = (0,15mm) of radius 1mm. You can use any Shape with the copper statement.
copper(LayerIndex(1)) = Line(1.0, [Point(0.0, -5.0) Point(5.0, -5.0)]) Create a 1mm wide copper line (results in a trace) on the 2nd copper layer from the top.

JITX Documentation