Until now, furnishing a board with the correct clearance constraints between the various objects used in design has, in more complex boards, proven to be a hair-pulling experience. Quite often an unwieldy number of clearance rules must be set up and correctly prioritized to achieve the desired result. And when importing design rules from another tool, such as PADS, a reasonable number of defined clearance rules can morph into a bloated bucket of such rules. With this in mind, Altium Designer 14.3 sees welcome refactoring applied to the Electrical Clearance rule, in the form of a 'minimum clearance matrix'.

Use the matrix to fine tune clearances between any objects in the design. In combination with rule-scoping, you have all the flexibility you need to build a concise and targeted set of rules to meet even the most stringent of clearance needs.

The provision of a minimum clearance matrix into the Electrical Clearance rule, allows for a far more manageable set of Clearance rules to be defined.

Definition of clearance values in the matrix can be performed in the following ways:

• Single cell editing - to change the minimum clearance for a specific object pairing. Simply click on a cell to select it for editing.
• Multi-cell editing - to change the minimum clearance for multiple object pairings:
  • Use Ctrl+click, Shift+click, and click&drag to select multiple cells in a column.
  • Use Shift+click, and click&drag to select multiple contiguous cells in a row.
  • Use click&drag to select multiple contiguous cells across multiple rows and columns
  • Click on a row header to quickly select all cells in that row.
  • Click on a column header to quickly select all cells in that column.

With the required selection made (either a single cell or multiple cells), making a change to the current value is simply a case of typing the new value required. To submit the newly entered value, either click away on another cell, or press Enter. All cells in the selection will be updated with the new value.

Example multi-cell editing.

At a summary level for rules, the Attributes field reflects whether the same minimum clearance value is being used throughout the matrix, for all object pairing combinations (in the form Clearance = <value>), or whether some object pairings have been modified with specific clearances (in the form Generic clearance = <value>, and <x> value(s) for objects.)

Indication that a matrix contains mixed clearance values is presented in the Attributes field on a rule summary page.