What is the driver IC?
LEDs are light-emitting diodes. When the number of diodes is large or the power consumption of tubes is large, they need to be driven, and they are driven in several stages. These stages are driven into an integrated electronic chip, which is called drive IC. In short, it plays the role of providing compensation current to diodes.
Working principle of LED Driver IC
The chip contains a constant current generation circuit, which can set the output constant current value through the external resistance. The switching time of the output channel can be controlled through the enabling end of the chip, and the switching frequency can be up to one megahertz (1MHz). The current output response is very fast, supporting the application of high color level change and high picture refresh rate. Built in open circuit detection, overheating, power failure and overcurrent protection functions greatly improve the reliability of the application system.
At present, the pulse drive chip supplies power to the LED lamp with the output interface of high-frequency pulse generator. Because the pulse signal frequency is very high, the human eye can not feel the stroboscopic of LED at all, so this method not only meets the visual needs, but also effectively saves electric energy output on the one hand. Moreover, the working frequency of this type of chip can generally be controlled by the external interface.
The adjustment method of the current value of the driving chip is mainly to change the brightness adjusted by the current value. Here, it is assumed that the brightness at the time of current change is 1 times, the brightness of white light and the brightness at the time of current change become 1.7 times, and the brightness at this time becomes 3 times. Although the illuminance is not proportional to the current value, the red light is proportional. The main reason is that the physical properties of red, green and blue chips are different from each other.
Development status of LED driver chips in China
As China’s LED driver chip industry started relatively late, the reserve of high-end technical talents is relatively insufficient, and there is a lack of talents with in-depth research in various disciplines such as optics, electricity and materials and rich experience in integrated circuit design. At the same time, the industry has developed rapidly in recent years. In order to meet the needs of rapid renewal and iteration of downstream LED lighting lamps, LED driven chip design enterprises need to continuously develop new products, so there is a relative shortage of high-end technical talents in the industry.
In recent years, the state has issued a series of industrial policies to support the development of LED driven chip industry. In 2014, the State Council issued the outline for promoting the development of national integrated circuit industry, pointing out that the integrated circuit industry is the core of the information technology industry and a strategic, basic and leading industry supporting economic and social development and ensuring national security, The next period will be an important strategic opportunity and critical period for the development of China’s integrated circuit industry. It is expected that by 2020, China’s integrated circuit design technology in some key fields such as mobile intelligent terminal and network communication will reach the world-class level.
Although China lags far behind in the technology of LED driver chips, it is believed that in the future, with the development of talents and applications, the prospect is still very broad.