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:
Feb. 07, 1984
Filed:
Sep. 08, 1982
Takashi Toyooka, Sayama, JP;
Hirokazu Aoki, Hachioiji, JP;
Mamoru Sugie, Sayama, JP;
Shigeru Yoshizawa, Tokorozawa, JP;
Hitachi, Ltd., Tokyo, JP;
Abstract
A series resonant drive circuit for a magnetic bubble memory includes X- and Y-coils arranged orthogonally to each other for generating a rotating magnetic field applied to a magnetic bubble memory chip, resonance capacitors each connected to a corresponding one of the X- and Y-coils for forming a series resonance circuit with the corresponding coil at a frequency of the rotating magnetic field, power supplies each connected to a corresponding one of the resonance circuits, and an inductance device connected in series with both of the resonance circuits and a capacitance device connected between the resonance circuits to compensate a mutual inductance due to the inductive coupling between the X- and Y-coils and a capacitance due to the capacitive coupling between the X- and Y-coils. Further, the temperature coefficient of the capacitance device is selected so that the temperature coefficients of the mutual inductance and capacitance between the coils can be compensated.