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:
Jan. 13, 1987
Filed:
Jul. 25, 1984
Mitsuo Ohsawa, Kanagawa, JP;
Sony Corporation, Tokyo, JP;
Abstract
A power supply circuit for supplying stabilized positive and negative DC voltages of opposite polarity but equal magnitude requires only a single voltage source that supplies a first DC voltage, and a polarity converting circuit connected to the voltage source provides a second DC voltage equal in magnitude but opposite in polarity to the first DC voltage. First and second voltage stabilizing circuits are connected to the voltage source and the polarity converting circuit, respectively, to provide between respective output terminals and a common ground line the equal level but opposite polarity voltages. Voltage stabilization is provided in the stabilizing circuits by the use of Zener diode circuits to provide biasing to control the collector-emitter paths of respective transistors, and polarity conversion is accomplished by a switching transistor controlled by a pulse-width modulation signal generator having its input derived from a level comparison circuit.