GB941889A - Improvements in or relating to circuit arrangements - Google Patents

Abstract

941,889. Circuits employing bi-stable magrietic elements. SIEMENS & HALSKE A.G. March 7, 1961 [March 7, 1960], No. 8372/61. Heading H3B. In a cross-point matrix each column and row wire to which a pulse generator may selectively be connected is held at a potential equal to or greater than that of the pulse applied by the generator until such time as the channel is connected by completing its circuit to earth. The invention is applied to the coincident selection of a magnetic core in a storage matrix M, such as shown in Fig. 2, where the row and column wires are pulsed by a generator such as I connected in common to the row or column wires over rectifiers R. Each matrix wire is held at the pulse potential over resistors W until the wire is chosen for energization by switching a transistor Tx particular to the wire to connect it to earth at its far end. The wires may be switched from both ends (see Fig. 4, not shown). Where the row and column wires are not driven directly but over transformers U (as shown in Fig. 3), the primary windings are held at the pulse potential over resistors W and are gated by transistors Tx. The arrangement is said to isolate unselected row and column wires from disturbing voltage changes otherwise produced as the result of the capacity of the transistor gates.