Patent ID: 9125260
Filing Date: 2015-09-01
Classification: H05B,Y02B

Abstract:
1. A control system for a feedback controlled LED driving circuit, the feedback controlled LED driving circuit being powered by a full-wave rectification unit rectifying an AC power signal to a sine-like DC power signal, the control system comprising: a valley detecting regulator unit electrically connected to the rectification unit, the valley detecting regulator unit receiving and analyzing the sine-like DC power signal; a power storage capacitor electrically connected to the valley detecting regulator, the power storage capacitor being charged by the valley detecting regulator unit with the sine-like DC power signal while the valley detecting regulator unit determines the voltage level of the sine-like DC power signal to be lower than a preset valley voltage; a system power supply unit electrically connected to the power storage capacitor, the system power supply unit receiving electric energy from the power storage capacitor and converting the electric energy into system required voltages for the control system; and a control and feedback unit electrically connected to the feedback controlled LED driving circuit, the control and feedback unit receiving a feedback signal from the feedback controlled LED driving circuit and accordingly generating a control signal to control an output current of the feedback controlled LED driving circuit for driving an LED element or to provide a protective measure thereto; wherein the control and feedback unit also connects to the valley detect regulator unit and receives a valley synchronous signal from the valley detect regulator unit, the valley synchronous signal generates in every valley of the sine-like DC power signal and starts a digital waveform for power factor correction, the control and feedback unit controls the output current of the feedback controlled LED driving circuit depending on the digital waveform.