| 摘要 |
PROBLEM TO BE SOLVED: To prevent increasing of a mounting space and mounting weight of a battery and turning out of a lighting fixture for vehicle due to a fall of a power supply voltage level at the time of starting or the like of an engine. SOLUTION: The control device of a lighting fixture for vehicle having light emitting elements 1, 2 each connected serially and a constant current circuit R1 is provided with a Zener diode ZD12 connected between a power source terminal VB and a grounding terminal GND, a first transistor Q1 of which the base is connected with an anode of the Zener diode and the connector is connected with the power source terminal, and the emitter is connected with the grounding terminal, a second transistor Q2 of which the base is connected with a collector and the power source terminal VB of the first transistor and the collector is connected with the power source terminal, and the emitter is connected with the grounding terminal, and a third transistor Q3 of which the base is connected with the collector of the second transistor and the collector is connected with a contact between the light emitting element and the constant current circuit, and the emitter is connected with a contact between the power source terminal and the constant current circuit. COPYRIGHT: (C)2011,JPO&INPIT |
