Abstract: In an automatic parking system, a marker recognizing unit performs recognition of a predetermined number of markers located respectively at predetermined locations in a parking garage. A marker deter miner performs determination of whether there is a problem in recognition of at least one marker in the predetermined number of markers in accordance with information resulting from the recognition performed by the marker detector. An output unit outputs marker state information resulting from the determination performed by the marker determiner.

Abstract: A lighting circuit turns on a plurality of semiconductor light sources. Multiple current sources are each coupled to a corresponding semiconductor light source. A switching converter supplies a driving voltage VOUT across each of multiple series connection circuits each formed of the semiconductor light source and the current source. A converter controller employing a ripple control method turns on a switching transistor of the switching converter in response to a voltage across any one of the multiple current sources decreasing to a bottom limit voltage.

Abstract: A lighting circuit turns on multiple semiconductor light sources. Multiple current sources are each coupled in series with a corresponding one from among the semiconductor light sources. A switching converter supplies a driving voltage VOUT across each of multiple series connection circuits formed of the multiple semiconductor light sources and the multiple current sources. A converter controller controls a switching transistor of the switching converter based on a relation between a voltage across one from among the multiple current sources and a reference voltage having a positive correlation with the temperature Tj.

Abstract: A lighting circuit turns on multiple semiconductor light sources. Multiple current sources are each coupled in series with a corresponding one from among the semiconductor light sources. A switching converter supplies a driving voltage VOUT across each of multiple series connection circuits formed of the multiple semiconductor light sources and the multiple current sources. A converter controller controls a switching transistor of the switching converter based on a relation between a voltage across one from among the multiple current sources and a reference voltage having a positive correlation with the temperature Tj.

Abstract: A lighting circuit turns on a plurality of semiconductor light sources. Multiple current sources are each coupled to a corresponding semiconductor light source. A switching converter supplies a driving voltage VOUT across each of multiple series connection circuits each formed of the semiconductor light source and the current source. A converter controller employing a ripple control method turns on a switching transistor of the switching converter in response to a voltage across any one of the multiple current sources decreasing to a bottom limit voltage.

Abstract: A lighting circuit turns on a plurality of semiconductor light sources. Multiple current sources are each coupled to a corresponding semiconductor light source. A switching converter supplies a driving voltage VOUT across each of multiple series connection circuits each formed of the semiconductor light source and the current source. A converter controller employing a ripple control method turns on a switching transistor of the switching converter in response to a voltage across any one of the multiple current sources decreasing to a bottom limit voltage.

Abstract: A lighting circuit turns on a plurality of semiconductor light sources. Multiple current sources are each coupled to a corresponding semiconductor light source. A switching converter supplies a driving voltage VOUT across each of multiple series connection circuits each formed of the semiconductor light source and the current source. A converter controller employing a ripple control method turns on a switching transistor of the switching converter in response to a voltage across any one of the multiple current sources decreasing to a bottom limit voltage.

Abstract: A lighting circuit turns on a plurality of semiconductor light sources. Multiple current sources are each coupled to a corresponding semiconductor light source. A switching converter supplies a driving voltage VOUT across each of multiple series connection circuits each formed of the semiconductor light source and the current source. A converter controller employing a ripple control method turns on a switching transistor of the switching converter in response to a voltage across any one of the multiple current sources decreasing to a bottom limit voltage.

Abstract: A lighting circuit turns on multiple semiconductor light sources. Multiple current sources are each coupled in series with a corresponding one from among the semiconductor light sources. A switching converter supplies a driving voltage VOUT across each of multiple series connection circuits formed of the multiple semiconductor light sources and the multiple current sources. A converter controller controls a switching transistor of the switching converter based on a relation between a voltage across one from among the multiple current sources and a reference voltage having a positive correlation with the temperature Tj.

Abstract: In an automatic parking system, a marker recognizing unit performs recognition of a predetermined number of markers located respectively at predetermined locations in a parking garage. A marker deter miner performs determination of whether there is a problem in recognition of at least one marker in the predetermined number of markers in accordance with information resulting from the recognition performed by the marker detector. An output unit outputs marker state information resulting from the determination performed by the marker determiner.

Abstract: A lighting circuit turns on multiple semiconductor light sources. Multiple current sources are each coupled in series with a corresponding one from among the semiconductor light sources. A switching converter supplies a driving voltage VOUT across each of multiple series connection circuits formed of the multiple semiconductor light sources and the multiple current sources. A converter controller controls a switching transistor of the switching converter based on a relation between a voltage across one from among the multiple current sources and a reference voltage having a positive correlation with the temperature Tj.

Abstract: A lighting circuit turns on a plurality of semiconductor light sources. Multiple current sources are each coupled to a corresponding semiconductor light source. A switching converter supplies a driving voltage VOUT across each of multiple series connection circuits each formed of the semiconductor light source and the current source. A converter controller employing a ripple control method turns on a switching transistor of the switching converter in response to a voltage across any one of the multiple current sources decreasing to a bottom limit voltage.