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:
Jul. 25, 2000
Filed:
Sep. 30, 1998
Hugh P Adamson, Boulder, CO (US);
Power Circuit Innovations, Inc., Boulder, CO (US);
Abstract
A dimmer ballast or output drive circuit and a drive method for a high intensity discharge lamp utilizes an overwound loosely coupled transformer having a turns ratio of preferably about one to one with a peaking capacitor across the secondary output terminals of the transformer and in parallel with the HID lamp arc electrodes. A control circuit provides a variable frequency drive voltage to the primary of the transformer. The frequency of the output voltage is adjustably controlled above the peak load power frequency. The load power and hence the light output of the lamp varies according to the frequency of the output voltage permitting a user to adjustably dim the high intensity discharge lamp.