Analyzing a CAM Document

PCB Design Check/Fix

To run a Design Rule Check for the current document, choose the Analysis » PCB Design Check/Fix command from the main menus. After launching the command, the PCB Design Check/Fix dialog will appear. The dialog lists a number of size and clearance constraints - including minimum annular ring - and also various DFM (Design For Manufacturing) constraints, such as Power/Ground Shorts, Double Drill Hits, and Net Shorts. Select which constraints you wish to check, enter the permitted tolerance (in mils) and decide whether or not the CAMtastic Editor should attempt to Auto Fix any encountered violations.

Use the Open and Save buttons to load/save DRC settings. Settings are stored in a CAMtastic DRC Settings file (*.drc).

Use the Reset button to restore permitted tolerances to their default settings - 5mil for all size-related constraints, with the exception of Part->Part Spacing, which is 10mil.

After setting up the DRC options as required, click OK to proceed with the check. If you have not yet extracted the netlist for the design, you will be alerted to this fact and netlist extraction will occur before the DRC continues. After the check is complete, an information dialog will appear, providing a violation summary. For each rule check, the number of violations Found, Fixed and Remaining are listed.

Permitted tolerances can be directly edited in the dialog. Alternatively, you can use the Analysis » Re-load DRC Rules from PCB command to load the respective tolerances (where applicable) from the design rules defined in the PCB document itself. After launching the command, the relevant design rule tolerances from the PCB document will be loaded into the Size (mils) column of the PCB Design Check/Fix dialog. The mapping of PCB design rule types to the corresponding DRC entries in the PCB Design Check/Fix dialog, are as follows:

Invalid Polygon Search

The Analysis » Invalid Polygon Search command is used to locate any invalid polygons within the current document. Polygons in a CAM document are continuous outlined boundaries that are Raster filled. Raster-filled boundaries cannot support overlapping or multiple shared vertices. Such instances are deemed invalid polygons and, if left unchecked, could cause undesirable results when photoplotting.

After launching the command the cursor will change to a small square and you will be prompted to "Select Draws". Simply drag a selection box around polygons in the design or, more efficiently, drag the selection box around the entire design. Once the selection is made, right-click. An information dialog will appear, either stating that No Invalid Polygons were Found, or that n Invalid Polygons were Found. In the latter case, the offending polygons will be assigned to the next unused Dcode and will become unfilled in the design space.

Creating a Fabrication Drawing (from Drill)

To create a fabrication drawing for the current document, using the drill layer(s) that are available, choose the Analysis » Create Fab Drawing (from Drill) command from the main menus. After launching the command the cursor will change to a small square and you will be prompted to select the closed border of the PCB design. Simply select the entire border (each line segment at a time) and then right-click. The Create NC Drawing dialog will appear.

The dialog is divided over two tabs. The PCB Information tab contains the overall dimensions of the PCB - automatically calculated from the selected PCB border - and several fields in which you can enter company information. The PCB Drawing Size tab allows you to specify the size of the fabrication drawing you wish to generate (standard sizes A-E).

After defining drawing options as required and clicking OK, a new layer - fablayer - is created and added to the layers list on the CAMtastic panel. This layer becomes the current layer, with all other layers that were ON before, now turned OFF.

The layer consists of symbols marking each different tool size used, and a legend, containing additional information for each hole size such as quantity, and whether they are plated.

Filling Boundaries

To fill selected closed boundary objects with optimized line strokes, choose the Analysis » Fill Boundaries command from the main menus. After launching the command, the cursor will change to a small square and you will be prompted to select closed boundary objects that you wish to fill. Simply position the cursor over part of the boundary for an object, and click. Continue adding objects to the selection and then right-click when done.

The Fill Boundaries dialog appears. Use this dialog to set up the options for the fill, including selection of layer for the fills to reside on, the minimum tool size to be used, and whether to limit the filling process to the use of one tool, or multiple tools.

After defining the options in the dialog as required, click OK to proceed. All selected boundaries will be offset inward until no further offset is possible (or one-time only if the Use Single Internal Offset option is enabled). The boundaries will then be filled with a line pattern, in accordance with the options defined.

Cleaning Boundaries

To fix the boundary of a polyline object, where the end points of the polyline are not precisely contacting to form a clean, closed boundary, but instead are crossing, choose the Analysis » Clean Boundaries command from the main menus. After launching the command, the cursor will change to a small square and you will be prompted to select polyline objects that you wish to fix. Simply position the cursor over the boundary of each polyline, and click.

The Join & Fix Polylines dialog will appear. Use the dialog to define options for joining the endpoints of the polylines.

After setting up the options as required, click OK to effect the fix. An information dialog will appear, reporting how many polyline objects were fixed (Closed) and how many were not (Open).

Generating Outlines

To create outlined boundaries from selected objects in the current document, choose the Analysis » Generate Outlines command from the main menus. After launching the command, the cursor will change to a small square and you will be prompted to select objects that you wish to generate outlines from. Simply position the cursor over individual objects and click to add them to the selection, or use one of the many selection tools available. After all objects are selected, right-click. The Vector to Outline dialog appears.

The top half of the dialog allows you to choose the style of outline that is created - either segmented, squared edges, or rounded edges.

You can choose to have the outline objects placed on the same layer, a new layer, or one of the existing layers. The Delete Old Objects option gives you the choice of keeping the original objects for comparison purposes.

Select the Dcode that you wish to use for drawing the outlines. You can choose one of the existing Dcodes defined in the current document, or use Polygon, or the default 0.005in (0.127mm) shape.

After setting the options as required, click OK to generate the outlines.

Querying Elements of a CAM Document

The commands of the Analysis » Query sub-menu are used to obtain information with respect to different elements of your CAM document:

• Analysis » Query » Object (shortcut: Q) – this command is used to obtain information with respect to a single selected object in the current document.

  After launching the command, the cursor will change to a pointing hand and you will enter object query mode. Simply position the cursor above the object that you wish to query, and click. Information relating to that object will appear on the Info tab of the CAMtastic panel. Information presented will vary depending on the type of object being queried and can include: Layer, Dcode related information, and object type.

  Continue interrogating further objects, or press Esc to exit query mode.

  When multiple layers are displayed, objects from different layers often overlap. Click repeatedly over such objects to cycle through each object, on each of the different layers involved. The information in the CAMtastic panel will update accordingly.

• Analysis » Query » Group – this command is used to obtain information with respect to a group of selected objects in the current document.

  After launching the command, the cursor will change to a small square and you will enter object query mode. You will be prompted to select objects to include in the query. Simply position the cursor over an object you wish to include in the selection, and click. Clicking away from an object allows you to drag a selection area, for including multiple objects in the selection. Selection is cumulative.

  Continue adding objects to the selection and then right-click when all required objects have been selected.

  Information relating to each object will appear, in separate folders, on the Info tab of the CAMtastic panel. Information presented will vary depending on the type of object being queried and can include Layer and Dcode related information.

  The order of the folders in the panel is determined by the order in which objects were added to the selection. In order to keep track of which objects you are querying, it is probably better to add objects to the selection individually, rather than using a selection box.

• Analysis » Query » Net (shortcut: Shift+N) – this command is used to obtain information with respect to a single selected net in the current document.

  After launching the command, the cursor will change to a pointing hand and you will enter net query mode. Simply position the cursor over an object that resides in the required net, and click . The entire net will become selected and information relating to that net will appear on the Info tab of the CAMtastic panel. The information includes the name of the net, the layer and type upon which it resides, and its total length.

  Continue interrogating further nets, or press Esc to exit query mode.

• Analysis » Query » Minimum Annular Ring – this command is used to interrogate the annular ring of the selected pad.

  After launching the command, the cursor will change to a pointing hand and you will enter annular ring query mode. Simply position the cursor above the pad whose annular ring you wish to query, and click. Values for the X and Y annular ring distances will appear on the Info tab of the CAMtastic panel.

  Continue interrogating further pads, or press Esc to exit annular ring query mode.

Measuring Distances

The commands of the Analysis » Measure sub-menu are used to measure distance between points, nets and objects in your CAM document:

• Analysis » Measure » Point to Point (shortcut: Shift+M) – this command is used to measure and display the distance between any two points in the current document.

  After launching the command, the cursor will change to a small cross, and you will enter measurement mode. Measurement involves the following sequence of actions:

  1. Position the cursor at the location where you wish to start measuring from, and click.
  2. Move the cursor to the end point and click again - as you move, a guide line will stretch from the start point to help you.
  3. Measurement information will appear on the Info tab of the CAMtastic panel, reporting the point-to-point distance measured, the coordinates of the start and end points, the X and Y distances, and the angle created from the horizontal.
  4. Continue measuring the distance between other points, or press Esc to exit measurement mode.

• Analysis » Measure » Net to Net – this command is used to measure and display the shortest distance between any two nets in the current document.

  First, ensure that the netlist for the design is available (on the Nets tab of the panel). You may need to extract the netlist first.

  After launching the command, the cursor will change to a small square, and you will enter measurement mode. Measurement involves the following sequence of actions:

  1. Position the cursor over an object that resides in the required first net and click.
  2. Move the cursor over an object in the required second net and click again. A visual connecting line will appear at the location where the distance between the two nets is the shortest.
  3. Measurement information will appear on the Info tab of the CAMtastic panel, reporting this shortest point-to-point distance, the coordinates of the start and end points of the connecting line, the X and Y distances, and the angle created from the horizontal.
  4. Continue measuring the distance between other nets, or press Esc to exit measurement mode.

• Analysis » Measure » Object to Object – this command is used to measure and display the shortest distance between any two objects in the current document.

  First, ensure that the netlist for the design is available (on the Nets tab of the panel). You may need to extract the netlist first.

  After launching the command, the cursor will change to a small square, and you will enter measurement mode. Measurement involves the following sequence of actions:

  1. Position the cursor over the first object and click.
  2. Move the cursor over the required second object and click again. A visual connecting line will appear at the location where the distance between the two objects is the shortest.
  3. Measurement information will appear on the Info tab of the CAMtastic panel, reporting this shortest point-to-point distance, the coordinates of the start and end points of the connecting line, the X and Y distances, and the angle created from the horizontal.
  4. Continue measuring the distance between other objects, or press Esc to exit measurement mode.