Modeling the impact of power/ground via arrays on power delivery

The impact of via arrays on power and ground planes is examined in This work. Measurements of the plane impedance were made on a 8×8 via array as a function of via pair location. The results from full-wave field solution are compared to measurement data and excellent correlation is obtained. The results show that the impedance and effective inductance is a strong function of location within the array. The lowest impedance and inductance is measured on the array perimeter. A 4 X increase in the impedance and inductance occurs at the array center. By parameterizing the antipad diameter in simulation it is found that the impedance increases sharply when the antipads overlap.