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. 09, 1995
Filed:
Apr. 29, 1993
Robert A Mammano, Costa Mesa, CA (US);
Larry Wofford, Cary, NC (US);
Unitrode Corporation, Billerica, MA (US);
Abstract
A pulse width modulator voltage feedforward circuit which includes a gating circuit for providing a control signal to a charge circuit which charges an integration circuit with a current proportional to an input voltage. The integration circuit provides an output ramp signal waveform having a slope proportional to the input voltage value. The gating circuit also provide a control signal to a discharge circuit, to thus alternately charge and discharge the integration circuit. The gating circuit insures that a minimum deadtime for a transformer reset will occur regardless of input voltage variations by preventing a fixed frequency signal provided by an oscillator from beginning a new ramp waveform signal period until the integration circuit is discharged to a minimum reference voltage level.