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:
Oct. 19, 1999
Filed:
Jun. 17, 1993
Shigeaki Wachi, Tokyo, JP;
Tetsuji Kawashima, Chiba, JP;
Sony Corporation, Tokyo, JP;
Abstract
A magnetic modulator coil driving circuit comprises: first and second switching elements for inverting the polarity of exciting currents supplied to magnetic modulator coils, first and second bias voltage setting circuit for determining control voltages to be applied to the first and second switching elements to adjust the currents flowing through the first and second switching elements to a predetermined value, and a data input circuit for supplying modulating data to turn on and off the first and second switching elements alternately. The magnetic modulator coil driving circuit applies a control voltage to the control electrode of the corresponding switching element to control the exciting current to be supplied through the switching element to the corresponding magnetic modulator coil so that the exciting current coincides with a desired value when a reference voltage is applied to the control electrode. Thus a fixed exciting current is supplied to the magnetic modulator coil so that the intensity of the magnetic field may not vary due to temperature variation in the magnetic modulator coil and the magnetic modulator coil may not overheat or burn.