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:
Nov. 07, 2000
Filed:
Sep. 30, 1999
Abstract
A piezoelectric transformer inverter includes: a piezoelectric transformer, one of whose primary electrodes is grounded, which performs voltage conversion of alternating voltage or direct current voltage applied between the primary electrodes and supplies the converted voltage to a load connected to a secondary electrode; a drive unit for supplying alternating voltage or direct current voltage between the primary electrodes of the piezoelectric transformer; a low-pass type resonance circuit unit inserted between the output of the drive unit and the primary electrodes of the piezoelectric transformer; a duty control unit for controlling ON-Duty of the drive unit so that a value of current flowing into the load coincides with a targeted current value; a phase-difference detection unit for detecting a phase difference between the input voltage and the output voltage of the piezoelectric transformer; and a frequency control unit for controlling a driving frequency of the drive unit.