Heating coil heating circuit for use in power supply unit of fluorescent lamp, has transformer whose windings are wound in same direction, where magnetic flow of transformer is dissipated over demagnetizing unit during stopping phase

摘要

The circuit has a series circuit comprising a primary winding (2) of a transformer and connected with an output of secondary windings (6, 7) of the transformer. The series circuit comprises rectifier diodes (8, 9) and output condensers (10, 11) to provide heating voltage to heat heating coils (13, 14). A controlling and regulating circuit part (muC) provides clock frequency for a clocked switch element (3). The windings of the transformer are wound in same direction, where magnetic flow of the transformer is dissipated over a demagnetizing unit during a stopping phase. The controlling and regulating circuit part is formed as an integrated circuit such as application-specific integrated circuit (ASIC) circuit.