Course design, design a LED light-controlled dimming circuit to adjust the brightness of the LED lamp by the change of visible light.
1. If you change 100K and LDR in the picture, you can achieve “the brighter the LED light is, the darker the LED light is.” To be more precise, change 100K down, about 10K.
2. The LED lamp can adjust the brightness. Switch dimming switch dimming is through the original lamp power switch for dimming, in the use and installation does not need to add any dimmer, as long as constantly press the number of times and speed of the original power switch can achieve the dimming of lighting lamps to meet the different brightness of personal needs.
3, the “light” dark day 10m daytime 1K, and 10K partial voltage, through the operational amplifier lm358 voltage comparison, so that the transistor on or off, control lamp on and off, the picture assumes that the led is a small led,vcc voltage is 5V.
How to adjust the light of tricolor lamp
The MOS tube is controlled by PWM to control the power on and off time of LED lamp to achieve the purpose of adjusting brightness. The above reference is from the article “trichromatic dimming LED desk lamp circuit”.
Just turn on the power drive, adjust the white and yellow wires for welding, and the color order of the tricolor LED lights will be adjusted. However, they have to have a certain hands-on ability, but also need electric iron, there is a certain degree of difficulty.
Take apart the interior of the led lamp and switch the bright white and yellow power cords.
You can adjust the order of the tricolor lamp by adjusting the power cord, first taking apart the interior of the LED lamp, and then exchanging the bright white and yellow power cord, which can not only change the color of the tricolor lamp, but also meet the needs of switching power.
Tricolor lamp adjustment order can adjust the plug order, the brightest and darkest lines can adjust each other to achieve tricolor lamp color change, but also to meet the needs of switching power. LED mainly uses cold light source, low power consumption and no radiation, and will not produce harmful substances in the process of using LED lamp.
What are the basic characteristics of led light source
Compared with the luminous effect of traditional light source, LED light source is a low-voltage microelectronic product, which successfully integrates computer technology, network communication technology, image processing technology and embedded control technology.
Light emitting diode (LED) is a new light source for indoor lighting, which is referred to as LED. The lighting usually used on video recorders (VCR) and car dashboards is LED. The LED has a life span of up to 1000000 hours and has no filament, so it will not generate heat or burn out.
The sixth point is that the led point light source has fast response time. LED light source has nanosecond response time, which is much better than ordinary lamps and lanterns. The seventh point is that led point light source has a very rich light color, it uses chemical modification and monochromatic light mixing and other different means to achieve a variety of color visible light band luminescence and discoloration effect.
After decades of technical improvement, the luminous efficiency of LED has been greatly improved. The light efficiency of incandescent lamp and halogen tungsten lamp is 12-24 lumens / watt, fluorescent lamp 50-70 lumens / watt, sodium lamp 90-140 lumens / watt, most of the power consumption becomes heat loss.
