Magnetic bubble domain memory chip with major/minor bubble path

Abstract

Magnetic bubble domain memory circuit design in which magnetizable overlay patterns of magnetically soft material, e.g. permalloy, are provided on a magnetic bubble-supporting magnetic layer to define bubble propagation paths including transfer gate elements and combined replicate/transfer gate elements. The replicate/transfer gate elements are operable in two modes either combining the replicate and transfer bubble functions in a first mode or operable to effect a bubble transfer function in a second mode, wherein a magnetic bubble is transmitted from one section of a bubble circuit propagation path to another. Processing of data through the use of the magnetic bubble domains may occur in a first-in/first-out basis in one embodiment and on a last-in/last-out basis in another embodiment of the bubble memory. A pulse generator is associated with the transfer gate and the replicate/transfer gate structures. The pulse generator associated with the replicate/transfer gate elements is controlled to deliver pulses in two different modes for respectively selectively actuating the replicate/transfer gate elements to perform the composite replicate/transfer function or the transfer function alone. The transfer gate elements and the replicate/transfer gate elements are configured to include head portions of pickax shape.