Broadside-Coupled Differential Routing In Package Via Pin-Field Design

Broadside-coupled differential routing is designed in via pin-fields for high-density packages. As compared with the standard edge-coupled differential routing, the proposed broadside-coupled routing reduces near-end crosstalk (NEXT) by nearly 10dB in the simulated 50GHz frequency range as a result of sixfold-widened inter-pair spacing in package breakouts. Other signal integrity (SI) properties including impedance matching, far-end crosstalk (FEXT), mode conversion and PN skew, are also characterized and compared. A design sizing shows that the proposed broadside-coupled configuration can use the same package construction as the edge-coupled counterpart and is an efficient approach that increases package routing density while maintaining desirable signal integrity for high-speed signals.