DRIVING DEVICE FOR SIGNAL LIGHT

摘要

PROBLEM TO BE SOLVED: To provide a driving device for a signal light effective for detecting a broken core wire of a light-emitting-diode type signal light. SOLUTION: Signal lights 41-4N are composed of light-emitting diodes connected in series and in parallel. A drive element 1 is connected to the signal light 41 in series to turn on/off a current supplied to the signal light 41. The sensor 21 of a current detection circuit 2 is connected to the signal light 41 in series to detect a current supplied to the signal light 41 and to output a current detection signal S1. A level detection circuit 22 detects the level of the current detection signal S1 supplied by the sensor 21 to output a level detection signal S2. A signal processing part 7 judges the presence or absence of failure of the drive element 1 and the signal light 41 by means of the logic of drive signals S31, S32 and the level detection signal S2.