| 摘要 |
<p>A signal is described herein that provides fight output for automotive, rail, ship traffic and/or illumination control that includes a light emitting diode (LED) array, wherein the LED array includes three groups of disparate colored LEDs. A power supply unit provides independent power to each of the three LED groups. Each LED group power supply unit includes an input controlled switch connected to a power line to provide power to the LED array. An input under voltage / over voltage circuit monitors the voltage level of the power line for enabling or disabling the input controlled switch according to the voltage level of the power line. A flyback transformer converts the power received from the power line from an alternating or a continuous current signal to a direct current signal output to the LED array. A dummy load draws power addltional to the LED array and a dummy load detection circuit monitors the dummy load to insure that the power drawn by the load is greater than or equal to a predetermined threshold. A light out detection circuit monitors the light output of the LED array via an optical sensor.</p> |
