What is the LED driver chip? How to choose? You must know these taboos for stage LED processing.

The VF voltage of the LED light source for illumination is very low, generally 2.75~3.8V, and IF is generally 15~1,400mA. Therefore, the output voltage of the LED driver IC is VFxN or VFx1, and the IF maintains a constant current of 15 to 1,400 mA. The LED light source used in LED lamps has two types of low power (IF is 15~20mA) and high power (IF is more than 200mA). Small power LEDs are often used to make LED fluorescent lamps, decorative lamps and grille lamps. High-power LEDs are used for home lighting, spotlights, underwater lights, wall washers, street lights, tunnel lights, car work lights, etc. The power LED light source is a low voltage, high current driven device whose luminous intensity is determined by the amount of current flowing through the LED. If the current is too large, the LED light will be attenuated. If the current is too small, the LED's luminous intensity will be affected. Therefore, the LED driver needs to provide a constant current power supply to ensure the safety of the use of high-power LEDs while achieving the desired luminous intensity. In the field of LED lighting, in order to reflect the characteristics of LED lamp energy saving and long life, it is very important to correctly select the LED driver IC. Without the matching of good driver ICs, the advantages of LED lighting cannot be realized.

1. The nominal input voltage range of the driver chip should meet the DC 8~40V to cover a wide range of application needs. The pressure resistance is preferably greater than 45V. When the input is AC 12V or 24V, the output voltage of the simple bridge rectifier will fluctuate with the grid voltage, especially when the voltage is high, the output DC voltage will also be high. If the driver IC does not have a wide input voltage range, it will often be broken down when the grid voltage rises, thus burning the LED light source.

2. The nominal output current requirement of the driver chip is greater than 1.2~1.5A. As an LED light source for illumination, the nominal operating current of a 1W power LED light source is 350 mA, and the nominal operating current of a 3 W power LED light source is 700 mA. A high-power LED light source requires more current. Therefore, the driver IC used in the LED lighting fixture must have sufficient current output. When designing the product, the driver IC must be operated at 70-90% of the optimal working area of the full-load output. Driver ICs that use full-load output currents are not well cooled in the narrow space of the luminaire, which can easily lead to fatigue and early failure of the luminaire.

3. The output current of the driver chip must be kept constant, so that the LED can be stably illuminated without flickering. The same batch of driver chips are used under the same conditions, and the output current should be as uniform as possible, that is, the dispersion is small, so that the production and the order can be ensured in the production of large-volume automated production lines. For the driver chip with a certain discrete output current, it is necessary to select the bin before the factory or put into the production line, adjust the resistance value of the current setting resistor on the PCB, and make the LED lamp constant current driving board to the same kind of LED. The brightness of the light source is uniform to maintain consistency in the final product.

In the previous stage performances, the functions of LEDs were relatively simple, mainly to display video data and synchronized video images. In the stage performances at the time, the stage workers did not include it in the scope of the dance, but regarded it as a big TV on the stage. Nowadays, as an extension and supplement of the stage performance, LED enriches the content of the performance and provides the audience with information beyond the performance itself. At the same time, the audience gets rid of a single, fixed perspective through the LED large screen, and can even see their own reactions, which also creates a certain sense of freshness in the visual.

Stage LED large-screen stage LED large screen can divide a picture into multiple video screens, the display can be independent, combined, any combination to play the relevant large background, large screen can be displayed according to the performance requirements, and can be realized The superimposition of the text, the background picture is played by the video signal processor or synthesized on the same screen display, the character can be played in close-up, the text can be scrolled, or the video can be played, the video screen can be horizontally moved, and the text can be raised and lowered to become text and personality. Video screen, lighting, beautifying the stage background and stage ground, through software design and system control to achieve other requirements, advantages, and frame structure design.

Easy to disassemble, reliable, easy to maintain applications and large entertainment venues and large event venues. However, convenient technical means does not really mean high efficiency. The comprehensive utilization of high-tech means on the stage does not represent a real improvement in the level of stage performance. Let's talk about the use of LED screens on the stage. A large-scale party that ignores the local LED screens. At the same time, many large-scale evening parties are on the scene, and most of them will propose the broadcast demand for live broadcast through TV. At this time, the creation team of the party should not only consider the effect of the live performance of the party, but also the characteristics of the communication of the TV.

In the traditional dance production, TV camera personnel can find the background image of the subject by using the background with low brightness or the background with large color difference in the background video to realize the unique TV picture art effect, but it is used in a large number of LED screens. Today, if you do not consider the needs of the TV lens at the beginning of the design, the final picture will lack a three-dimensional sense. The main body and the background will be easy to fit and overlap, and the effect of TV transmission will be greatly reduced. The basic components of a TV screen are shots of different scenes. In simple terms, it is a panoramic view, a medium shot, and a close-up. The live performances are more of a "panoramic" effect. Many creative teams often only consider the “big effect” of the panorama when they are making the dance design. They don’t think about the medium scene, especially the close-up, that is needed when the TV is transmitted.

Abusing the real-life picture The continuous improvement of the LED display manufacturing technology has made many production teams and organizers love the characteristics of the screen "HD". In the process of creation, it is easy to enter the "missing big mistake" misunderstanding. In order to reflect the characteristics of the high-definition screen as much as possible, the producer is often keen to play a special live video on the live video wall as a background dance. For example, in the song and dance program, a large number of urban landscape pictures and human life pictures are played, and it is intended to achieve a combination of program art interpretation and screen reality presentation, but the result is counterproductive. The stage show performance pursues a high sense of form, with color, light, and formation as the longest, and most of the live-action videos are too rich in color, which will be used as the main background of the stage, but will be interpreted in the form of the stage program. It brings great damage, and the audience has a sense of clutter that “can’t see” and “do not know where to look”. The original design used to enhance the effect of the program has a huge impact on the audience’s viewing. The basic principle of the beauty of the design and production of the program.

Abuse of LED screens, destroying lighting effects, LED screen production and use costs are gradually reduced, so that many creators blindly pursue the concept of "panoramic video beauty", the use of LED screens in the beauty design, and even more, all dance scenes are used LED instead. However, many creators have neglected the reality that LED screens are easy to bring great light pollution to the stage. When the stage is finished designing and performing overall lighting synthesis, it has been regretted. In the overall design of the program, the lighting plays a huge role, it can make the whole stage a magical sense of space and layering, making the overall visual presentation more interesting and interesting. In the traditional stage dance beauty design, the only light source is the lighting system. The director, the lighting engineer and the dancers can work together to create a unique stage space.