Patent ID: 7466083

Claim:
A protective device for a vehicle electronic apparatus, which includes an inverter for converting a direct-current voltage into an alternating-current voltage for the vehicle electronic apparatus, the protective device comprising: a temperature detecting means for detecting a temperature of the inverter; a control means for controlling a power supply of the direct-current voltage to the inverter, the control means stopping the power supply to the inverter when the temperature of the inverter reaches a predetermined temperature; a frequency detecting means for detecting a frequency of the alternating-current voltage, which is generated by the inverter, wherein: the vehicle electronic apparatus further includes a liquid crystal panel and a light source for backlighting; the alternating-current voltage is applied to the light source for backlighting to light the light source; and the control means further stops the power supply to the inverter when the frequency of the alternating-current voltage changes; a signal wire connecting the frequency detecting means and the control means to apply pulse signals corresponding to the alternating-current voltage to the control means; and a switching means for connecting the signal wire to a fixed voltage part when the temperature of the inverter reaches the predetermined temperature.