Effects of magnetic keepers on Permalloy-film stores

Calculations of magnetic fields and transmission-line reactances have been carried out for the word and sense lines of a thin-film plated-wire store configuration under various conditions of keeper thickness and permeability. Since keeper proximity and thickness shape the applied field distributions, it helps to increase the bit-packing density and affects the word- and digit-driving currents. The induced e.m.f., noise coupling and propagation delays on the line have also been derived. These parameters greatly influence the store performance characteristics, and must be considered in store design.