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.
Automotive lamp
2023-03-21
Patent
Electronic Resource
English
IPC: | H05B ELECTRIC HEATING , Elektrische Heizung / B60Q ARRANGEMENT OF SIGNALLING OR LIGHTING DEVICES, THE MOUNTING OR SUPPORTING THEREOF OR CIRCUITS THEREFOR, FOR VEHICLES IN GENERAL , Anordnung von Signal- oder Beleuchtungsvorrichtungen, deren Einbau oder Halterung oder deren Schaltkreise bei Fahrzeugen allgemein / F21S Ortsfeste Leuchten , NON-PORTABLE LIGHTING DEVICES / F21W Index-Schema in Verbindung mit den Unterklassen F21K, F21L, F21S und F21V, betreffend den Gebrauch oder Einsatz von Leuchten oder Beleuchtungssystem , INDEXING SCHEME ASSOCIATED WITH SUBCLASSES F21K, F21L, F21S and F21V, RELATING TO USES OR APPLICATIONS OF LIGHTING DEVICES OR SYSTEMS / F21Y Index-Schema in Verbindung mit den Unterklassen F21K, F21L, F21S und F21V, betreffend die Form oder die Art der Lichtquellen oder die Farbe des emittierten Lichts , INDEXING SCHEME ASSOCIATED WITH SUBCLASSES F21K, F21L, F21S and F21V, RELATING TO THE FORM OR THE KIND OF THE LIGHT SOURCES OR OF THE COLOUR OF THE LIGHT EMITTED |