![]() And when it comes to Fill, Region, and Polygon objects, most users just see these as more 'copper.' With this in mind, the minimum clearance matrix for the Clearance rule has been enhanced to operate in two modes: Working with the Clearance Matrixįor many users, there is no great difference between Track and Arc primitives. When creating a subsequent new clearance rule, the matrix will be populated with the values currently defined for the lowest priority Clearance rule. The default Clearance rule for a new PCB document will default to use 10mil for all object-to-object clearance combinations. Minimum Clearance Matrix - provides the ability to fine-tune clearances between the various object-to-object clearance combinations in the design.Conversely, when a different clearance value is entered for one or more object pairings in the matrix, the Minimum Clearance constraint will change to N/A, to reflect that a single clearance value is not being applied across the board. A value entered here will be replicated across all cells in the Minimum Clearance Matrix. Minimum Clearance - the value for the minimum clearance required.Ignore Pad to Pad Clearances within a footprint - toggle this option on/off to specify whether clearances between pads in the same component footprint are ignored.If the via and SMD pad must touch or overlap, you also need to define a suitable Via Under SMD design rule (High Speed category) and enable the Allow Vias under SMD Pads constraint. Even if a via and SMD pad are connected with a trace or overlapping, they are deemed to be in violation when the distance between them is less than the Via-SMD Pad clearance in the Same-Net Clearance rule.Ĭonfigure the minimum distance allowed between a via and SMD pad by setting the Via-SMD Pad clearance in the Same-Net Clearance rule. When a via and SMD pad have soldermask clearance, and the two are too close together, the soldermask bridge between the two objects can disappear and solder paste will flow down into the via during the soldering process, creating a bad solder joint on the SMD pad. The exception to this is when checking the clearance between via and SMD pad objects in the same net. connected), then they are not deemed to be in violation of the rule. ► Learn more about Differential Pair Clearance Checkingįor a defined Same-Net Only Clearance rule, the general approach is that if two objects are touching (i.e. Use this constraint to configure the clearance when the nets in the differential pair must be closer together than allowed by the general clearance. Same Differential Pair - constraint is applied between any two primitive objects belonging to the different nets in the same differential pair (e.g.Use this constraint to configure the clearance between the differential pairs. The rule does not apply between primitives in the two nets in the same differential pair (eg, DiffPair1_P and DiffPair1_N). a track in DiffPair1 and a track in DiffPair2). Different Differential Pair - constraint is applied between any two primitive objects belonging to different nets of different differential pairs (e.g. ![]() This is the most comprehensive of the three options and covers the possibility of the objects belonging to the same net, or different nets. Any Net - constraint is applied between any two primitive objects belonging to any net in the design. ![]()
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