| 摘要 |
A semiconductor circuit (6) for driving a light emitting diode, which is responsive to an application of an output voltage from a rectifying circuit to emit a light, comprising a switching element (10) connected between the light emitting diode (5) and a ground potential; an input voltage detecting circuit (21) for detecting the output voltage from the rectifying circuit (2) to output a light emission signal or a light quench signal; a current detecting circuit (18) for detecting a current flowing through the switching element (10); and a control circuit for intermittently controlling, at a predetermined oscillation frequency, the on/off of the switching element (10), based on the output signal from the current detecting circuit (18), while the input voltage detecting circuit is outputting the light emission signal. |
