Abstract: A power-saving and stabilizing ballast includes a bridge rectifier circuit, an electrolytic capacitive filter circuit, a half bridge inverter circuit, and an LC output circuit, all of which are sequentially and electrically connected. An EMC filter circuit is electrically connected between a voltage input port and the bridge rectifier circuit for restraining high frequency currents from damaging electric power. A power factor correction circuit is electrically connected between the bridge rectifier circuit and the electrolytic capacitive filter circuit for enhancing power factor, reducing harmonic and achieving a constant power output. An abnormal state protection circuit is electrically connected to the half bridge inverter circuit for protecting the ballast against damage from abnormal states. The ballast is also capable of resisting transient spikes or strong thunder and lighting interferences from electric power, and suppressing surge currents effectively.

Abstract: A power-saving and stabilizing ballast includes a bridge rectifier circuit, an electrolytic capacitive filter circuit, a half bridge inverter circuit, and an LC output circuit, all of which are sequentially and electrically connected. An EMC filter circuit is electrically connected between a voltage input port and the bridge rectifier circuit for restraining high frequency currents from damaging electric power. A power factor correction circuit is electrically connected between the bridge rectifier circuit and the electrolytic capacitive filter circuit for enhancing power factor, reducing harmonic and achieving a constant power output. An abnormal state protection circuit is electrically connected to the half bridge inverter circuit for protecting the ballast against damage from abnormal states. The ballast is also capable of resisting transient spikes or strong thunder and lighting interferences from electric power, and suppressing surge currents effectively.