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:
Apr. 26, 1994
Filed:
Feb. 21, 1993
Yoshio Fukushima, Mino, JP;
Matsushita Electric Industrial Co., Ltd., Kadoma, JP;
Abstract
A power-supply unit having a rectifier circuit, switch, first and second voltage generation circuits, a control circuit, and a capacitor. The rectifier circuit is connected to an A.C. power source. The switch opens/closes an electric line which supplies a load circuit with electric power from the A.C. power source via the rectifier circuit. The first voltage generation circuit generates a first voltage based on an output voltage of the rectifier circuit. The first voltage is a non-zero voltage. The second voltage generation circuit generates a second voltage based on the output voltage, and is larger than the first voltage. The control circuit turns the switch on when the output voltage is in a range between the first voltage and the second voltage, and turns the switch off when the output voltage is outside the range. The capacitor is charged with electricity by the output voltage when the output voltage is in the range, and supplies the load circuit with electric power when the output voltage is outside the range.