What is the driving mode of LED driving IC?

LED driver IC. In recent years, liquid crystal displays of portable electronic products such as mobile phones and digital cameras are mostly changed to color panels. Liquid crystal displays themselves are passive light-emitting elements, and they must be illuminated by the backlight module to read the image of the panel. The prospect is 1996. After Professor Nakamura released blue light, the three primary colors were finally ready, with excellent photoelectric characteristics, and the price continued to fall. White light has become the main lighting source of portable electronic products. But in fact, the lighting of white light requires a high direct voltage and a large driving current, so driving the backlight module with high efficiency becomes the driving index. Then, the white light driving technology is discussed, and the white light application circuit is introduced.

The driving method is to adjust the current value and pulse amplitude modulation technology. The current value is mainly adjusted by changing the brightness of the current value. Here, it is assumed that the brightness is 1 times, and the brightness of white light is 1.7 times when the current changes, and the brightness is 3 times. Although the illuminance is not proportional to the current value, the red light is proportional. The main reason is red, green and red.

Direct voltage of white light tends to be unevenly distributed with different types, resulting in uneven brightness distribution of white light. How to make the brightness uniform is one of the driving technical indicators. In addition, white light is usually used in portable electronic products with batteries as the main power supply, so providing low-power power supply is the second priority of white light driving. Secondly, it has the function of automatically adjusting the brightness according to the use environment. For example, white light application products can automatically detect the brightness of the surrounding environment and adjust the appropriate brightness in the hot sun environment. The function of automatic brightness adjustment can not only improve the visibility of the LCD panel, but also benefit the service life of the battery. List of white light driving core technologies, white light driving consists of digital technology and analog technology respectively, and digital technology is mainly used for control and illumination sensor control; Analog technology is an indispensable technology for boost circuit and current control circuit. In the past, white light was mostly driven in parallel, but parallel connection was prone to uneven brightness. As mentioned above, if the brightness is proportional to the driving current, it can be replaced by series driving, because the internal current remains unchanged, so the problem of uneven brightness can be solved. The above-mentioned white light driver integrates the analog technology of the boost switch circuit and the digital technology of the current control circuit. In other words, one optical driver can control the actions of three light sources, such as the backlight module of the main picture and the sub-picture of the LCD panel and the flash of the digital camera. The total dynamic source of the three systems is less than 40Am.