Electrical modelling of enhanced ball grid array packages using coupled transmission lines

Frequency-domain S-parameter measurement techniques are used to establish t he high-frequency/high-speed equivalent circuit models of enhanced ball gri d array packages. By considering the longest coupled traces of the packages , the coupled transmission-line parameters found include the characteristic impedance, coupling coefficient and propagation delay. The equivalent lump ed models have been further derived from coupled transmission line models u sing the concept of distributed circuits.