Working with Backdrilling in Allegro PCB Designer: Best Practices
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Example - A trace connects two pins on Layer 2. An electrical stub is present from
the bottom layer up to the surface of Layer 2 because there is no other connections
made below Layer 2. Backdrilling from the bottom side of the PCB will remove the stub
by drilling beyond Layer 3 and stopping in the dielectric material before hitting Layer 2 to
meet the electrical stub requirements. Doing this will violate the manufacturing minimum
plating depth requirement and the connector pin will no longer have a reliable
connection to the PTH.
Tool Tip – When backdrilling from both sides of the PCB for Press Fit Connector pin
locations, the BACKDRILL_PRESSFIT_CONNECTOR property should be used.
Min Pin Plating
