Patent ID: 6570505
Filing Date: 2003-05-27
Classification: G08G,H05B

Abstract:
In a light-emitting-diode lamp, the improvement comprising an input impedance-changing circuitry for establishing a low input impedance circuit of the light-emitting-diode lamp when said light-emitting-diode lamp is turned off, said input impedance-changing circuitry comprising:a shunt circuit section including a low impedance element and a controllable switching device connected in series; and a detector circuit section comprising means for detecting turning off of the light-emitting-diode lamp and means for closing, in response to detection of turning off of the light-emitting diode lamp, the controllable switching device in order to establish a shunt circuit including the low impedance element and thereby establish said low input impedance circuit of the light-emitting-diode lamp.