Design Of Single Wire Of LED Lamp Dimming Devices

With electronic light source entered in the daily life, traditional electronic light source is replaced for LED, such as incandescent light bulb, energy saving bulb. In order to cater for trend of energy saving, the control of LED luminance has gained high attraction in these years. Nowadays, the luminance of LED could be usually adjusted by two different modes:remote control mode and digital control mode. In remote control mode, the control of one-to-one regulation is needed, which give rise to high cost and trouble of management. On the other hand, in digital control mode, although the weaknesses of remote control are solved, as result of laying new cable, it also takes higher cost and heavier work. By exploiting this problem, single wire control mode has been proposed without complex management and higher cost. However, single wire control mode which has existed has four levers of luminance and can not meet people’s demand.A new method using single wire switch to control the LED bulb is proposed in this paper, this single wire switch connect two button switches on wall and diode which can form the parallel circuit to control the light increase and decrease, and this can also parallel connect the bidirectional trigger diode, bidirectional triggered thyristor and circuit of phase-shifting angle size in series resistance. This method can control the alternating voltage positive half-wave and negative half-wave so as to regulate luminance by receiving signal. When the increased brightness of switch is disconnected and the decreased brightness of switch is closed, phase-shift trigger generate on the positive half-wave. At the same time, the micro control receive the signal of increased brightness and transform it to the driver signal of increased brightness, then the brightness of LED is increase. When the decreased brightness of switch is disconnected and the increased brightness of switch is closed, the phenomenon is opposite.Digital potentiometer which is used to adjust the brightness of the LED solution is proposed. The program uses two buttons to switch the switch on the wall after a series of positive and negative, respectively diode in parallel and the control by a single FireWire change in luminance signal is supplied directly. The method of controlling switch AC voltage with positive and negative half-wave is missing by two wall push button switches; the control circuit generates a LED lamp brightness increases or decreases. When the closure brightness reducing brightness increase switch off switch, AC negative half-wave increases luminance signal is received by the missing generation digital potentiometer, triangle wave and triangular wave generator to generate a PWM signal is compared, and then control the LED brightness increases; When the switch is closed off to increase the brightness reduce brightness switch, AC positive half wave missing generated reduced luminance signal is received by a digital potentiometer, triangle wave and triangular wave generator to generate a PWM signal is compared, and then control of the LED brightness is reduced.In the circuit of adjusting the microcontroller brightness of LED bulb, brightness of LED bulb can change the value from 0% to 100% by the step of 0.1%, with the functions of automatic dimmer. The smaller phase-shifting angle is, the greater stability of the circuit is and the stronger anti-interference ability is. In the circuit of adjusting the brightness of Digital potentiometer LED bulb, the brightness can change the value from 0% to 100% by the step of 1.43% with multi-stage (infinite) dimming function, and can automatically store the last LED lamp brightness and direct recovery. There is no problem that the program may run fly and circuit has the ability of stabilization and strong anti-interference without the micro-controller in circuit. Two schemes are controlled by single wire, without having to lay cables. The devices of circuit are smaller size, designed simply and lower cost.