| 摘要 |
PURPOSE:To fabricate a light emitting diode type lamp which can be activated on either AC or DC power supply and on DC power regardless of polarity by circuit arrangement which can always apply voltage of preset polarity to a light emitting diode activated on power supply of either AC or DC of any polarity. CONSTITUTION:A light emitting diode 3 can light in a normal way when positive DC voltage is applied to the input terminal 6 and negative DC voltage to the input terminal 7 because positive voltage can be applied to the cathode of the light emitting diode 3 through a resistor 5 and a diode D1, while negative voltage can be applied to the anode of the light emitting diode 3 through a diode D3. On the other hand, the light emitting diode is still lighted in the normal way when positive DC voltage is applied to the input terminal 7 and negative DC voltage to the input terminal 6 because positive voltage can be applied to the cathode of the light emitting diode 3 through a diode D2 and negative voltage can be applied to the anode of the light emitting diode 3 through the resistor 5 and a diode D4. |
