| 摘要 |
PROBLEM TO BE SOLVED: To prevent lighting of a warning lamp or a display lamp in a moment by a stored charge of a power source stabilizing capacitor with a simple circuit structure when an ignition switch is turned to OFF state from ON state and power source supply to a vehicular display device is shut off. SOLUTION: A constant voltage diode 15 having a predetermined Zener voltage intervenes in a base current supply path of an NPN type transistor 13 for lighting and driving the warning lamp (light-emitting diode) 11 for informing abnormality of a vehicular control device 30 such as an air bag control device or an ABS (antilock brake system) control device, and thereby a lighting threshold voltage whereby the NPN type transistor 13 is turned on is raised. When the power supply voltage of the vehicular display device 10 is lowered to the lighting threshold voltage or less at a point of time when an NPN transistor 32 on the vehicular control device 30 side is turned off, the transistor 13 for lighting and driving is prevented from being turned on, and thereby the warning lamp (light-emitting diode) 11 is prevented from being lit. COPYRIGHT: (C)2005,JPO&NCIPI
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