PACKAGE TO PRINTED CIRCUIT BOARD TRANSITION

Package to printed circuit board (PCB) transitions are described. In one aspect, a multi-layer PCB (100) includes an external layer (L01) having a transition region (110) configured to receive an electrical component (IC) and a clear routing region (160) outside of the transition region (110). The PCB includes first via(s) (231,232) that extend from the transition region (110) to an inner trace routing layer (L02). The trace routing layer is disposed between the external layer (L01) and the second inner trace routing layer (L04). The first inner trace routing layer (L02) includes a transition area (110) disposed under the transition region (110) of the external layer (L01), a clear routing area (160) outside of the transition region (110), and a transmission line (150) that connects a given first via (231,232) to a second via (141) for a second electrical component. The transmission line (150) includes conductive trace(s) that each have a first width (150B) in the transition area (110) and a second width (150A), greater than the first width (150B), in the clear routing area (160).