FILAMENT CUTOUT CIRCUIT

摘要

The invention provides a filament cutout circuit for a fluorescent lamp (60). The filament cutout circuit includes a filament transformer (20) with a primary winding (22) and at least one secondary winding (24, 26, 28), and a cutout transistor (30) serially connected to the primary winding (22). The secondary winding (24, 26, 28) provides a filament voltage to a filament (62, 64) in the fluorescent lamp (60). A filament control input (12) turns on the cutout transistor (30) for a predetermined time period to preheat the filament (62, 64).