To improve stability in brightness of a semiconductor light source.SOLUTION: A lighting circuit 400 includes a current source 410 and a thermosensitive element 402. The thermosensitive element 402 detects the temperature T of a semiconductor light source 302. The current source 410 has a positive correlation with the temperature T when the temperature is in a normal range, and generates a drive current Ihaving a negative correlation with the temperature T in a high temperature range where the temperature T is higher than that in a normal range.SELECTED DRAWING: Figure 1
【課題】半導体光源の輝度の安定性を改善する。【解決手段】点灯回路400は、電流源410および温感素子402を含む。温感素子402は、半導体光源302の温度Tを検出する。電流源410は、温度Tが正常範囲であるとき、温度Tと正の相関を有し、温度Tが正常範囲より高い高温範囲において、温度Tと負の相関を有する駆動電流ILEDを生成する。【選択図】図1
LIGHTING CIRCUIT AND VEHICLE LIGHTING FIXTURE
点灯回路および車両用灯具
2020-01-23
Patent
Electronic Resource
Japanese
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 |