Fluorescent lamp energy-saving electronic ballast circuit

Electronic ballasts have the characteristics of wide operating voltage range, fast starting, no noise, no flicker, and energy saving. It has been
accepted by more and more people. The circuit shown in the figure is a typical circuit of a popular electronic ballast currently on the market .
    In Figure 10-3, VD1~VD4, c1, and G form a bridge rectifier and filter circuit to complete the conversion of AC zov to DC 300V. Ma and
Feng are the starting resistors, which provide the initial conduction bias voltage for VT2, thereby stimulating VT1 and VTZ to form high-frequency self-excited oscillation. B is
the self-induction choke generated by the voltage reduction, and C3, VD5, VD6, and G form a soft start circuit, which delays the establishment of the circuit
operating point and lengthens the preheating of the lamp filament to facilitate the rapid starting of the lamp. , extend its service life.