LED is undoubtedly the hottest application at present. Whether it is handheld devices , game consoles, neon lights, billboards, etc., dazzling colors and high-quality light can always attract people's attention. In the face of many current LED controllers, how to choose a feature-rich and cost-effective product to cater to your own design is undoubtedly a problem for every designer.
The simplest LED driver , we can use ordinary I / O to achieve. However, I/O control can only achieve LED ON and OFF, can not be used for mixing, flickering, etc., and each LED needs to occupy a separate I / O resource, no doubt the price is very low. We can also design with a dedicated high-current LED controller, but the expensive cost will first become a problem, and the design is complex, and the degree will be correspondingly increased with the occurrence of various interferences. Based on this, NXP has introduced a series of LED drivers using I2C interface, which can control ON/OFF, flicker and RGB mixed light from 4 to 24 LEDs simultaneously through two lines of I2C interface. . In a mixed-light scheme, each LED is driven by a separate 8-bit/256-order PWM. Currently, each LED current that can be driven by the chip itself ranges from 25 mA to 100 mA. Of course, for some high current applications, we only need to use the external field effect tube to achieve.
This I2C-based LED control method increases the convenience and flexibility of the design, and also reduces the investment in hardware and software, making the LED in mysterious appearance seem simple and wonderful for us. Below, we will take the NXP LED driver PCA9633 as an example to explain the advantages of this LED driver through several simple applications.
The PCA9633 is a quad LED driver that can drive up to 25mA per channel and provides an optional fixed I2C address and a 4-bit or 7-bit hardware programmable hardware address depending on the package (Figure 1).
Figure 1: Schematic diagram of the pin and internal structure of PCA9633
From Figure 1, we can see that each LED is controlled by a single 8-bit/256-order PWM, and because the PWM is fast enough, it can theoretically mix any color through the four LEDs it drives. Light. In addition to each individual PWM, the PCA9633 also provides a Group PWM, which allows us to control the brightness and frequency of the blended color, making up for some functions that only a single PWM can't. So how exactly does the PCA9633 implement dimming? The secret is still on the PWM. If you do not use PWM, then it can only complete the opening and closing action; low-speed PWM can only achieve LED flashing, not enough to achieve the purpose of color mixing; high-speed PWM can achieve RGB color mixing; if PWM speed is controllable, then Dual functions of flickering and color mixing can be achieved. And through the controllable 8bit/256-order PWM, the color gradation is increased to enhance the layering of color (see Figure 2).
3D curved full coverage Samsung Tempered Glass is easy to fit with your phone. And full coverage AB glue Samsung Screen protector don't splash when it cracked. HD clear smooth as silk and comfortable touch feeling can provide you original experience. 9H scratch resistant can protect your phone from being scratched by hard objects. Nano waterproof Oleophobic coating can magically resist dirt, sweat and annoying fingerprints.
For Model No: Samsung Galaxy S9 Plus, Samsung Galaxy S9, Samsung Galaxy S8 Plus, Samsung Galaxy S8, Samsung Galaxy Note 8, etc.
Pls feel free to contact us if you are interested in these products, have any questions or special needed. We have the best sales team to service to you.
Look forward to your inquiry, and welcome to visit our factory.
Samsung Tempered Glass
Samsung Tempered Glass,Anti Blue Light Tempered Glass For Samsung,Samsung Tempered Glass Screen Protector,Hd Tempered Glass For Samsung
Shenzhen Kantou IM Technology Co., Ltd. , http://www.kantou-im.com