| 摘要 |
A LED lamp with an integrally build-in a function for preannouncement end of life time in a LED lamp per se and to realize the LED lamp having such function with simple construction and at low cost. The LED lamp system has an alternating current power source connecting portion for receiving an alternating current, a power source converting portion for receiving the alternating current and rectifying the received alternating current for generating a direct current power, LED group consisted of a plurality of LEDs and received a direct current power output from the power source converting portion, the LED group having a life time preannouncement portion for integrating power supply period for issuing preannouncement indicative of approaching to the end of the life. The life time preannouncement portion includes counting means for measuring the power supply period on the basis of a frequency of the alternating power source, integrating means for integrating the power supply period measured by the counting means and storing the integrated value in a non-volatile memory, and power supply mode control means for controlling illumination of LEDs at different modes including a normal lighting modes, the power supply mode control means being responsive to an integrated value of the integrating means in excess of a predetermined criterion to operate in a predetermined life time preannouncement mode.
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