Patent ID: 6255785
Filing Date: 2001-07-03
Classification: H05B

Abstract:
A high power factor electronic ballast with low lamp current peak ratio comprising; a bridge rectifier for rectifying a commercial power supply voltage, a high frequency oscillator using an output voltage from said bridge rectifier as its supply voltage, and a first supplementary power source to supply said high frequency oscillator a voltage by superimposing two supplementary voltages generated from a portion of high frequency current in a load on said output voltage from said bridge rectifier a second supplementary power source to supply said high frequency oscillator a direct offset voltage generated from a portion of high frequency current in the load to improve an input current waveform of said bridge rectifier, said second supplementary power source including a diode and a capacitor having its one terminal connected to a load terminal linked with the load and said first supplementary source power and another terminal connected to a voltage output terminal of said bridge rectifier and linked with one terminal of said diode, said diode being connected serially in a feed branch from said bridge rectifier to said high frequency oscillator with said another terminal connected to said oscillator.