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:
Aug. 08, 1978
Filed:
Sep. 15, 1977
Kenneth N Bergan, Minnetonka, MN (US);
Control Data Corporation, Minneapolis, MN (US);
Abstract
A current drive circuit for deriving a triangular current waveform for driving an inductive load, such as the field coils of a bubble memory, comprises a series of at least four diodes connected between the positive and negative input voltage lines. A pair of switching devices, such as switching transistors, are connected in series such that each switching device is in parallel with two of the diodes. The junction between the switching devices is also connected to one output for the inductive load. The intermediate diodes are connected together and to one side of a time delay circuit, the opposite side of which is connected to the second output for the opposite side of the inductive load. A modification of the invention comprises a second diode and switching circuit connected between the time delay circuit and the second output.