Issue link: https://resources.pcb.cadence.com/i/1180264
Working with Backdrilling Backdrilling October 2019 14 Product Version 17.4-2019 © 1999-2020 All Rights Reserved. Figure 1-4 Minimum Pin Plating Applying the Minimum Pin Plating Property The BACKDRILL_MIN_PIN_PTH property can be applied to symbols or pins using Edit – Properties. It prevents backdrill passes from removing a stub based on the relation between the and the Must Not Cut Layer using the following criteria: ■ If the lower surface of the Must Not Cut Layer (Connection Layer) is outside the minimum pin plating depth, backdrilling will occur to eliminate the stub. Else the layer pair will be shifted down one layer so backdrilling could occur. ■ If the remaining stub after the layer pair shift violates BACKDRILL_MAX_PTH_STUB property for the net then the pin will be flagged with a "P" symbol indicating a stub exists but the pin could not be backdrilled due to the plating restriction. The Allegro PCB designer, when assessing P code violations, is advised to: ■ Consider rerouting the signals on other layers to reduce the stub length while maintaining minimum pin plating requirements. ■ Consult with engineering and discuss the possibility of increasing the value of the BACKDRILL_MAX_PTH_STUB property on the affected nets. ■ Create a new backdrill pass set to accommodate the targeted layer to backdrill to.