Abstract: A magnetic bubble domain package in which a magnetic bubble domain chip is bonded to conductors disposed on a thin film interconnect member which is formed to allow a reduction in the volume of the drive coils of the package. The conductors of the interconnect member are bonded to a lead frame which provides signal leads for the magnetic bubble domain chip and the drive coils. The interconnect member with magnetic bubble domain chip and lead frame bonded thereto is encapsulated with a molding compound, the chip being located precisely within the mold in order to insure placement of the chip in the geometric center of the drive coils. The drive coils are prewound and slipped onto the premolded package through slots formed during the molding process to reduce the volume of the coils, and the coils terminated directly onto the signal leads of the lead frame.

Abstract: Method and apparatus for testing and setting the field strength of permanent magnets in a magnetic bubble domain chip module, wherein the final molded module is formed to contain a pair of longitudinal slots which run through the module on opposite sides thereof. The module is inserted, via said slots, onto conducting members of a magnetic bubble module testing apparatus. The conducting members effectively provide one turn coils on each side of the module. Current is induced in these coils in such a way as to either add to or subtract from the bias field provided for the magnetic bubble domain chip by the permanent magnets of the module. The module is tested to determine the upper and lower operating levels of the bias field for effective operation of the chip, and the device is remagnetized to set the bias field of the module in the center, or optimal point, of the bias margin.