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. 29, 1981
Filed:
Sep. 29, 1980
Peter K George, Morgan Hill, CA (US);
Saleem Akhtar, Groton, MA (US);
National Semiconductor Corporation, Santa Clara, CA (US);
Abstract
In a field-access magnetic bubble memory X and Y coils encircle the chip for providing the rotating XY magnetic drive field when conventional drive signals are applied thereto. At least one of the coils is non-uniformly wound to provide a first predetermined magnitude of the drive field in first predetermined chip areas and a second lesser predetermined magnitude of the drive field in a second chip area. In the embodiment disclosed the chip has a dual-block replicate architecture with gates and bubble detectors requiring a relatively high drive field located in peripheral edge areas at the bottom and top of the chip. A plurality of data storage loops requiring a relatively low drive field are located in the medial portion of the chip. The outer layer of the Y coil is non-uniformly wound to provide a gap in registration with the medial area of the chip. As a result, the magnitude of the drive field is higher in the peripheral edge areas than in the medial storage area, making possible a reduction in coil power consumption.