Issue link: https://resources.pcb.cadence.com/i/1526746
MANUAL CONSTRAINT ENTRY VS. CONSTRAINT SETS Sometimes you need a constraint value applied to one specific object (trace width, SMD pin spacing, etc.). In this part of the example, we will apply a constraint value manually and then examine the benefit of doing that versus using blanket constraint sets. 14. Enter 0.070 in one of the column cell values (e.g., under the column Thru Pin To - All). Notice how all the other cells go to ***'s. This is fine. There is no need to modify them either because they just indicate that not all the values within the constraint set are the same. 15. Now that I manually entered a new value (0.070 mm) for my Thru Pin To - All spacing cell, any time I use the BGA-REGION constraint region on an area of the PCB, it will apply that rule to that area of the PCB. 16. However, let's click on the original spacing constraint set for this BGA. Go back to Spacing - Spacing Constraint Set - All Layers, then the worksheet opens. 17. Notice that all the rows and columns still have the same value (0.076) and our higher level constraint set, SCS_ BGA-REGION has not adopted the new spacing value I put in one of the cells in the BGA-REGION worksheet cells. Why is that? 18. Higher-level constraint sets, such as SCS_BGA-REGION, do not adopt manual lower-level entries. This behavior allows you to apply these constraint sets to any number of objects or groups first, then later, lets you set more specific constraints that are unique to certain objects. That is, we can swap in and swap out constraint sets at any time to any object or region for convenience. 19. We won't go deeper into that, so for now, let's reapply the SCS_BGA-REGION constraint set to our spacing region. 24 www.cadence.com Part 1 of 5