LIGHTING SYSTEM OF INSTRUMENT FOR VEHICLE

PROBLEM TO BE SOLVED: To prevent an LED for illumination of an instrument for a vehicle from instantaneously going out when a tail lamp switch is turned off. SOLUTION: A control signal outputted from an ILL_LO terminal of a microcomputer 100 and a signal from a tail switch 400 are inputted to a transistor 602 via an OR circuit 500. When the tail switch 400 is turned off, the microcomputer 100, until detecting turning off of the tail switch 400, outputs a low-level control signal from an ILL_HI terminal to a transistor 601 and outputs a high-level control signal from the ILL_LO terminal to the transistor 602. The microcomputer 100, on detecting the turning off of the tail switch 400, inverts the logic level of each control signal. Thus, the transistors 601 and 602 are not simultaneously turned off when the tail switch 400 is turned off, so that the instantaneous going out of the LED 200 can be prevented. COPYRIGHT: (C)2004,JPO&NCIPI