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:
Jan. 30, 2001
Filed:
Oct. 16, 1998
Mihail S. Moisin, Brookline, MA (US);
Electro-Mag, International, Inc., Scituate, MA (US);
Abstract
A ballast circuit for energizing a lamp includes an inverter circuit with a start up circuit which provides a repeating start up sequence until a lamp lights. The start up circuit includes a start up switching element coupled across a start up capacitor which initiates operation of the inverter. A rapid start capacitor is charged as the inverter applies a signal to the lamp and the voltage on the rapid start capacitor determines the conduction state of the start up switching element. The inverter applies an increasing strike voltage to the lamp until the lamp lights or until the lamp voltage becomes greater than a predetermined level. After the restart capacitor discharges, the start up capacitor charges to re-initiate operation of the inverter. The ballast thereby applies a strike voltage to the lamp having a relatively small duty cycle for reduced stress on the circuit components.