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. 01, 2013
Filed:
Jan. 18, 2012
Nitin Kumar, Burlington, MA (US);
Shashank Bakre, Woburn, MA (US);
Driss Baba, Swampscott, MA (US);
OSRAM SYLVANIA Inc., Danvers, MA (US);
Abstract
A ballast for dimming a lamp is provided. The ballast includes an inverter circuit for providing a lamp current for energizing the lamp and a dim interface for receiving an input indicative of a selected lighting level. A control circuit is connected to the dim interface for generating a pulse-width-modulated signal having a duty cycle corresponding to the selected lighting level. A switching network is connected to the control circuit for receiving the pulse-width-modulated signal. The switching network operates between a conductive state and a non-conductive state as a function of the pulse-width-modulated signal. An impedance device is connected across the switching network and is configured for connecting in series with the lamp so that the impedance device receives the lamp current when the switching network is operating in the non-conductive state and the lamp current bypasses the capacitor when the switching network is operating in the conductive state.