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:
May. 05, 2015
Filed:
Jan. 11, 2012
Masatsuru Miyazaki, Tokyo, JP;
Hidetaka Yoshihashi, Tokyo, JP;
Masatsuru Miyazaki, Tokyo, JP;
Hidetaka Yoshihashi, Tokyo, JP;
FDK Corporation, Tokyo, JP;
Abstract
The polarity detection circuit includes a first diode with anode receiving a first phase of the AC power supply voltage and a second diode with anode receiving a second phase, opposite the first phase. The detection circuit further includes a constant-voltage power supply outputting a positive constant voltage. A first reference-voltage output circuit outputs a voltage corresponding to the constant voltage when the AC voltage of the first phase is positive, and outputs a voltage at a cathode of the second diode when the AC voltage of the first phase is negative. The detection circuit also includes a first signal output circuit that compares a first voltage, corresponding to a voltage at the cathode of the first diode, and a voltage output from the first reference-voltage output circuit and that outputs a signal indicative of polarity of the AC voltage having the first phase according to a comparison result.