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:
Mar. 28, 2006
Filed:
Jan. 13, 2003
Guenther W. Wimmer, West Linn, OR (US);
David L. Knierim, Wilsonville, OR (US);
Guenther W. Wimmer, West Linn, OR (US);
David L. Knierim, Wilsonville, OR (US);
Xerox Corporation, Stamford, CT (US);
Abstract
A circuit for controlling a piezoelectric transducer includes an N-channel FET having a gate electrode, a drain electrode coupled to a high voltage signal source Vpp, wherein Vpp is a positive going pulse train, and a source electrode coupled to an output Vcntrl for controlling the transducer and a charging circuit, responsive to a low voltage input signal Vpp_sel, for charging the FET gate to a bias voltage greater than the FET's threshold voltage while Vpp is near zero volts and for maintaining the bias voltage on the FET gate while Vpp ramps up to a value greater than the bias voltage and until Vpp_sel is removed. The control circuit reduces switching time and reduces current spikes in the power supplies to the chip.