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:
Oct. 09, 1979
Filed:
Sep. 22, 1978
Kenneth P Holmes, Austin, TX (US);
Esquire, Inc., New York, NY (US);
Abstract
A dimmer circuit for an HID lamp is provided for supplying a square wave current therethrough at a constant frequency, but whose duty cycle is variable dependent on a sensed current level. The circuit employs a first pair of transistor switches for reversing polarity through the lamp at a low frequency rate. Associated with each of those transistors is a circuit having a transistor switch connected to a drive circuit employing a timer network. The timer network produces an output that is a square wave, the leading edge of which occurs at regular intervals at a high frequency rate. The trailing edge occurs dependent on a dim/bright voltage setting and upon the amount of current through a sensing resistor in series with the lamp.
Data source: USPTO (United States Patent and Trademark Office) public patent records. Weekly synchronization. How IDiyas builds this profile