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:
Feb. 16, 1999
Filed:
Sep. 04, 1997
Dale G Hall, Cedar Crest, NM (US);
James R Phillips, Albuquerque, NM (US);
Gary L Vaughn, Albuquerque, NM (US);
Donald Forst, Albuquerque, NM (US);
Harold W Mech, Albuquerque, NM (US);
Motorola Inc., Schaumburg, IL (US);
Abstract
A piezoelectric transformer with voltage feedback is disclosed. The transformer comprises a piezoelectric plate of predetermined length, width and height with a driving section formed by alternately stacking a plurality of piezoelectric ceramic layers having internal interdigitated electrode layers. A driven section including an unpolarized dielectric section, a voltage feedback section in the form of a multilayer electrode structure or an outer strip, and a normally polarized dielectric section is also disclosed. The transformer generates an output voltage at an output terminal by the piezoelectric vibration transmitted from the driving section. A feedback control circuit is connected to the voltage feedback section. The isolated voltage feedback provides feedback control to keep the transformer operating at the proper resonant frequency even as there is a change in output load of the transformer.