| 摘要 |
<p>(Project) For the installation/removal of an LED lamp of an LED lighting device, safe work can be done even if a power voltage is received. (Solution) The LED lamp is physically installed in or removed from a power supply device (2) for supplying DC power to an LED lamp. The power supply device (2) includes a detection resistor (R3) detecting a current flowing through the LED lamp, a current feedback control part controlling a constant current by comparing a current detection value of the detection resistor (R3) to a predetermined reference value, a voltage feedback part reducing a voltage of the power supply device to a safety voltage, and a semiconductor switch element (M2) connected between the LED lamp and the detection resistor (R3). A removal state of the LED lamp is detected as a drain voltage of the switch element (M2). [Reference numerals] (2) Power supply device;(AA) Current feedback control unit;(BB) Pyramidal wave oscillator;(CC) Voltage feedback control unit;(DD) Third reference voltage;(EE) First reference voltage;(FF) First voltage comparison unit;(GG) Second voltage comparison unit;(HH) Second reference voltage</p> |
