In order to obtain a relatively large color range, in the LED color mixing design, the control method of using current or voltage on one side is switched to intelligent technology such as microcontroller or field programmable gate array (FPGA), such as various color selection and operation. Real-time adjustment of color accuracy during the process. The LED color mixing design faces two obstacles, namely, the inconsistency of each LED parameter and the change of the performance of the LED with temperature, which requires that the LED model specification and temperature compensation must be considered in the LED color mixing design. However, this kind of compensation is not only complicated, but also requires the design engineer to have a more professional knowledge of color theory. There is a quick and easy way to use an LED color mixing design based on the Cypress EZ-Color controller.
The EZ-Color controller is a programmable system-on-chip for high-brightness LED color mixing applications. It is mainly composed of 8-bit microprocessor, programmable analog and digital modules and external hardware multiply accumulators, IC, Flash, SRAM and other peripheral modules. Mixing designs with the EZ-Color controller requires the help of Cypress's codeless graphical design software, PSoC express. PSoC express is an in-line system design tool that doesn't require design staff to write code. The tool itself runs at the system level rather than the design level. It uses a special function rather than a circuit, and the function itself is a real device, but a sensor, a thermistor or an LED driver.
The EZ-Color controller consists of input, output drive and transfer function relationships. The implementation mechanism of the color mixing scheme is shown in Figure 1. It can be seen from Fig. 1 that the 9 EZ-Color color mixing scheme uses (y, y, Y) as an input, and the output is an RGB three-color LED. The hardware driver for the tri-color LED uses a random signal forced modulation (SSDM) user module. The input (x, y, Y) represents the color input request information of EZ-Color according to the representation method of the CIE 1931 chromaticity diagram, that is, x, y represents hue and color saturation, and reflects color chromaticity information; and y represents luminous flux, Reflects the brightness information of the color. The SSDM User Module is a hardware implementation of Cypress's Precision Illumination Signal Modulation (PrISM) technology. PrISM technology is a special LED brightness adjustment technology superior to the traditional PWM method, which can effectively solve electromagnetic interference and low frequency flicker problems.
Figure 1 EZ-Color solution implementation block diagram
The combination of EZ-Color controller and software PSoC express fit has fundamentally changed the threshold for enterprises to enter the LED market. This solution not only eliminates the need for operators to learn color mixing (a discipline that requires a lot of input and complexity), and does not require the creation of multi-dimensional look-up tables for components such as thermistors or LED product grading. The more outstanding advantage is that EZ-Color can complete these tasks in just a few minutes. With this LED color mixing technology, there is no need to implement C language coding, and the language used in the simulation itself simulates standard lighting technology. The new color mixing scheme not only has the characteristics of high integration, low cost, flexibility and ease of use, but also effectively solves the problem of low frequency flicker and electromagnetic interference.
Edit: Nizi
300W LED Parking Lot Light,Slip Fit Mount Parking Lot Light,LED Parking Lot Lighting,Outdoor Street Parking Lot Lighting
Vietnam JJ Lighting Company , https://www.vnjjlighting.com