The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Dec. 25, 1979
Filed:
Sep. 05, 1978
Sidney J Schwartz, Vista, CA (US);
Burroughs Corporation, Detroit, MI (US);
Abstract
Circuitry for use in bubble memory propagation wherein field drive coils receive energy from an energy storage device (capacitor) through a plurality of selectively located and timed switches. A basic digitally controlled switching arrangement is illustrated in matrix form and, in one embodiment, one capacitor with two voltage sources and, in another embodiment, two capacitors and a single voltage source are utilized. Selective timing of the opening and closing of the switches provides a digitally controlled series of 1/2 sine wave current pulses to meet operating requirements for bubble propagation. Additional variations of the selective timing of switch opening and closings are used to elongate the start and stop pulses to provide better operating margins for these events. Field rotation in either clockwise, or counter-clockwise, or a mix of rotational senses is readily achieved under digital control.