Copper Connection PCB Software Tips

Here are a bunch of tips. Check back occasionally to see newly added ideas.

Add Your Favorite PCB Files to the Gallery

There are multiple ways to add a file to the Gallery:

1. Open the file normally, either in the Gallery or the editor (such as File→Open). The most recently opened files are automatically added to the Gallery.

2. Or, drag and drop one or more files from Windows Explorer to the Gallery window.

Drag and drop files to the Gallery

Drag and drop files to the Gallery

3. Or, my personal favorite, right-click in the Gallery and choose Add All Files from a Folder. All of the PCB files in the folder (and in subfolders) are added to the Gallery. This is the fastest way to add your entire library.

Bulk adding files to the Gallery

Bulk adding files to the Gallery

Add a Point to a Trace or Polygon

There are multiple ways to add a point:

1. Double-click on the polygon edge or the trace

2. Or, right-click on a trace or polygon and choose Add Point

Right click on a trace to add point

Right click on a trace to add point

3. Or, if you have enabled Show Add Points in the View menu, then plus-sign boxes appear when a trace or polygon is selected. Dragging the plus-sign box adds a point.

Click on plus sign box Drag to add a new point

Click on plus sign box and drag to add a new point


Start of Drag Determines Grid Alignment

When dragging a group or selection of elements, the element you click on to begin the drag will be aligned to the grid. For example, let's say you have a capacitor with leads that are 2 mm apart, but both the grid and snap are set to 0.1 inch. Only one pin is going to sit squarely on the grid.

Capacitor with 2 mm lead spacing on tenth inch grid

Capacitor with 2 mm lead spacing on tenth inch grid

If you click on the first pin and drag the part elsewhere on the board, then the first pin will end squarely on the grid, as expected.

Begin drag on pin 1 end with pin 1 on grid

Begin drag on pin 1 -- end with pin 1 on grid

Instead, what if you want the second pin aligned to the grid? Click on the second pin and drag.

Begin drag on pin 2 end with pin 2 on grid

Begin drag on pin 2 -- end with pin 2 on grid

What if you begin the drag on the part outline or text? For example, the plus sign...

Begin drag elsewhere end with apparent misalignment

Begin drag elsewhere -- end with apparent misalignment

Neither pin is directly lined up with the grid because the software snapped to the portion of the part that you started on (in this case the upper left corner of the text '+'). Keep this in mind if the software seems to be fighting your effort to place a particular hole in a particular place. Because current software lacks the ability to read your mind (coming soon), you need to indicate by starting the drag on your focus element.


Images

Images can be added from files using the Image tool or copied and pasted from a paint program. They can be converted to polygons (vector art) to appear on manufactured boards. See Adding Images to a PCB for complete information.


Microsoft Excel Text Format Error

One of the more powerful features of Copper Connection is the ability to copy the element data as text. The data can be edited manually and then pasted back in.

Excel is a useful tool for this purpose, except that it can misinterpret certain text as a formula or reference. For example, the text "+V" is misunderstood by Excel as a reference to a cell name "V". Excel shows an error of #NAME?.

To prevent this problem, perform the following steps.

  1. Select the desired elements in Copper Connection
  2. Choose Copy Special from the Edit menu
  3. Open up a new workbook in Excel
  4. Paste
  5. Select the columns Name, Description, and Text (click on the column header)
  6. Change the format from General to Text
  7. Click in cell A1
  8. Paste (again)
  9. Now Excel interprets those columns as text
  10. Make desired changes
  11. Select All (click in the upper-left corner of the spreadsheet -- above 1 and to the left of A)
  12. Copy
  13. (Let's say you are going to replace those elements) In Copper Connection, delete the selected elements by pressing the delete key
  14. In Copper Connection, Paste

Changing Hole Inner-Layer Connection Symbols

Four layer boards have inner layers. Those inner layers are usually used for large copper planes -- one for ground and one for positive voltage. Therefore, Copper Connection automatically includes a copper pour on those layers. (It is your responsibility to connect the layer to the appropriate power source.)

To connect to a pour on an inner layer, right click on a hole and choose Pad Connections. Choose either a solid or thermal connection.

Copper Connection shows a ground symbol for holes connected to the Inner Layer Upper and a plus sign for holes connected to the Inner Layer Lower.

Hole symbols indicate connections to pours on inner layers

Hole symbols indicate connections to pours on inner layers

If you want to choose a different symbol, right-click on the specific inner layer name on the Layer Colors and Visibility window.

Right click on inner layer name to change pour connection label

Right click on inner layer name to change pour connection label

Sample File

Choose Example PCBs from the Help menu to locate the file named "Pad Connections Examples". There are notes on the board that describe the different ways to connect holes. Move the cursor over the notes to see the tips.

Here are some things you should play with in order to see layer connectivity:

  1. Turn the board over
  2. Show/hide individual layers in Layer Colors & Visibility
  3. Show/hide Automatic Board Pours in the View menu
  4. Change pour connection symbols

Editing Solder Mask

Solder mask is an electrically-insulating coating that is applied to the top and bottom of the board except where you want to solder or make electrical contact. For example, solder mask is applied over traces, but not over pads. Solder mask is usually applied by a PCB manufacturer, if the manufacturer offers that option.

Solder mask provides three benefits:

  1. Avoids accidental electrical contact due to stray wires, loose screws, and so on
  2. Reduces oxidation or other chemical reactions
  3. Eases soldering by repelling solder from the coated portions of the board. This is why solder mask is often called solder resist.

Copper Connection creates the solder mask automatically by adding an edge-to-edge pour between board edges and then erasing all of the pads. To see the solder mask:

  1. Choose Board Properties in the File menu. Click the board tab. Make sure top and bottom solder mask is checked.
  2. Choose Layer Colors and Visibility in the View menu. Make sure top and bottom solder mask is checked.
  3. Check Show Pours and check Show Automatic Board Pours.

You can remove additional solder mask, such as to make conductive button contacts:

  1. Choose a drawing tool (say a polygon)
  2. Choose the desired solder mask layer from the Shape section of the main ribbon
  3. Choose Keep Out Fill from the Shape section of the main ribbon
  4. Draw in the board.

To add solder mask, follow the same steps as above, but choose Fill instead. Then, right-click on the newly drawn shape, choose Pour Connections, and select None (connected to Pour).

See Silkscreen and Solder Mask for photos and complete information.


Non-Plated Through Holes (NPTH)

There are two industry issues with unplated holes:

1. There is no official way of indicating non-plated holes in industry-standard (Gerber/Excellon) files.

2. Depending on the manufacturing technology, plated holes and non-plated holes require different manufacturing steps. Plated holes are drilled with an oversize drill at the beginning of the manufacturing process. Non-plated holes must be drilled with the correct size drill, and are either tented with resist film or must be drilled at the end of the process.

PCB prototype runs are optimized for efficiency (fewest steps and maximum automation). Therefore, most manufacturers do not offer non-plated holes in prototypes. Manufacturers usually offer non-plated holes in a custom or full-service order, where the manufacturer can provide the extra attention and handling, for an extra price.

If a non-plated hole is absolutely essential for a prototype, there is a workaround. Include a smaller plated hole in the PCB design. Then, after receiving the boards, you can manually drill the hole to the finished size. The smaller plated hole both acts as a pilot hole and reduces the amount of material you need to remove yourself.

In a future version of Copper Connection, there may be a way to indicate a hole is non-plated. But, somehow the software needs to indicate non-plated holes to the manufacturer. Because the industry standard file format doesn't provide a way to do so, there is a likelihood that the board will not turn out as the user expects. This can ruin a batch of boards.

For example, here are two possible approaches and their potential pitfalls:

1. Split the drill file into plated and unplated holes. One manufacturer's website says "If you send us PCB files with split plated and non-plated holes files, the non-plated holes file will be ignored."

2. Use a single drill file, but don't place a pad around the hole and allow the solder mask to overlap (tent).

  1. The manufacturer may place the order on hold, as a hole without a sufficient annular ring triggers most automated design rule checks.
  2. The manufacturer may automatically add an annular ring, resulting in a short circuit with nearby design elements.
  3. The manufacturer may treat all the holes the same, drilling them all oversize (to compensate for plating). The plating won't stick to the holes without pads -- resulting in oversized mounting holes.

Therefore, the current recommended approach for production boards with non-plated holes is to talk to your chosen manufacturer. Provide them with the exported files as usual, along with the locations of non-plated holes. They will then mark up the files appropriately for their manufacturing equipment.

Fill vs Pour

For rectangles, arcs, ellipses, and polygons, you can choose Fill or Pour in the Shape section of the main ribbon. On the screen, Fill and Pour initially look the same, but behave differently with respect to other elements.

Fill does not leave a gap around other elements -- pour does.

Fill and Pour do not behave the same

Fill and Pour do not behave the same