Issue link: https://resources.pcb.cadence.com/i/1180288
Allegro/OrCAD Rigid Flex Design Creation Best Practices _______________________________________________________________________ Learn more at Cadence Online Support - https://support.cadence.com Page 38 © 2016 Cadence Design Systems, Inc. All rights reserved worldwide. The InterLayer Checks This section of the document focuses on the interlayer checks. Overview In typical Rigid Flex designs, the creation of various masks, bend areas, stiffeners, and so on require special clearances or overlaps of materials and spacing. These objects are represented on specific subclasses that require a verification process to ensure that the clearances and overlaps are properly met. In 17.2, Allegro PCB Editor provides the ability to perform a check on geometries that exist on two different Class/Subclasses. The InterLayer Checks that perform this task are defined in Allegro Constraint Manager. Inter-layer checks can be run as part of the on-line DRC process, set as a batch process or turned off. This is accomplished by using the Constraint Analysis Modes Design Options for On-line InterLayer Checks. Using InterLayer Check Rules The basic interlayer rule definition requires two different Class/subclasses, a choice of four rule types, and how the DRC marker should be displayed. The four checks available in the InterLayer Check definitions are: Gap Overlap 1 Inside 2 2 inside 1 Gap When two objects on different subclasses need to be a minimum distance apart, the Gap rule is used to perform that check. For example, the edge of any Stiffener in the design must be a minimum of 1.27mm away from a Bend_Area. To enable a Gap check: 1. In Constraint Manager->Spacing->Inter Layer->Spacing form, select the subclasses for BEND_AREA and STIFFENER_BOTTOM. 2. Select the rule type as Gap. 3. Define the minimum gap value. 4. Select the checkbox to show a DRC marker if this condition is violated. 5. Specify a character for the DRC marker character. In this case, use G to represent Gap. 6. Specify the Display layer. For example, INTER_LAYER. Alternatively, add a note to inform users of the intent of the rule.