| 摘要 |
PROBLEM TO BE SOLVED: To provide a circuit in which the brightness of an LED lamp is maintained at a more constant level, while prolonging the circuit life, and the life of the LED lamp is notified.SOLUTION: In a constant voltage/constant current circuit for LED introducing a three-terminal regulator and a Zener diode, where a rectifier circuit for rectifying by means of a diode bridge is connected with a light-emitting diode circuit, the light-emitting diode circuit is connected with an input terminal of the three-terminal regulator, a resistor is connected with an output terminal of the three-terminal regulator, the other end of the resistor is connected with the diode bridge, and the ground of the three-terminal regulator is connected between the diode bridge and the resistor. The Zener diode includes a constant voltage constant current circuit connected between the light-emitting diode circuit and the input terminal of the three-terminal regulator, and further connected between the resistor and the diode bridge in parallel and reverse bias with the diode bridge. |
