A comparison of metals and ferrites for high-speed pulse operation

Metals and ferrites with rectangular hysteresis loops are used in magnetic amplifiers, switching networks, and data-storage systems. In these applications, the large-signal pulse response is most important. To reduce the effect of eddy currents, metals have been rolled to ultrathin gauge and high-resistivity ferrites have been used. By these techniques, eddy currents have been reduced to the point where relaxation effects limit the response time in both cases. The relative merits of metals and ferrites indicate that at present ultrathin metal-ribbon cores are better for stepping registers and switching circuits, while ferrite cores are better for use in coincident-current memories.