|LED dot matrix display screen features--programmable message display video led panel|
The combined LED dot matrix display uses a light-emitting diode as a picture element, which is arrayed by a high-brightness LED chip, and then encapsulated by an epoxy resin and a mold. It has high brightness, low power consumption, few pins, large viewing angle, long life, moisture resistance, cold and heat resistance, corrosion resistance and so on.
The dot matrix display has two types of monochrome and two colors, which can display red, yellow, green, orange, and the like. The LED dot matrix has 4×4, 4×8, 5×7, 5×8, 8×8, 16×16, 24×24, 40×40, etc.; according to the number of pixels, etc., the two primary colors , the three primary colors, etc., according to the color of the pixel, the color of the text, image and other content displayed is different, the single primary color dot matrix can only display fixed colors such as red, green, yellow and other monochrome, dual primary color and three primary color dot matrix display content The color is determined by the combination of different color LEDs in the pixel. If the red and green are bright, yellow can be displayed. If the lighting time of the diode is controlled in a pulse mode, 256 or higher gray scale can be realized. Display, you can achieve true color display.
The internal circuit structure and appearance specifications of several LED dot matrix displays. The structure and pins of other types of dot matrix can be tested. When the LED dot matrix display is used in a single block, it can replace the digital tube to display digital digits. Chinese and Western characters and symbols, such as 5 x 7 dot matrix display for displaying western letters, 5×8 dot matrix display for displaying Chinese and Western languages, 8 x 8 dot matrix for displaying Chinese characters, and also for graphic display. Large-screen displays can be constructed by combining multiple dot-matrix displays, but such practical devices are often driven by a microcomputer or a single-chip microcomputer.
It can be known from the internal structure of the LED dot matrix display that the device should be operated by dynamic scanning driving. Since the LED dies are mostly of high brightness type, the single LED driving current of a row or a column can be selected with a narrow pulse, but the average current Should be limited to 20mA, the positive voltage drop of the single LED of most dot matrix displays is about 2V, but the forward voltage drop of the dot matrix display single LED of the large bright spot ∮10 is about 6V.
The large-screen display system generally combines small modules consisting of multiple LED dot matrixes in the form of building blocks. Each small module has its own independent control system. When combined, only one total control is introduced. The controller can control the commands and data of each module. This method is simple and easy to display and easy to maintain.
There are two types of display modes for each module in the LED dot matrix display system: static and dynamic display. The static display principle is simple and convenient to control, but the hardware wiring is complicated. In practical applications, the dynamic display mode is generally adopted. The dynamic display works by scanning, and is driven by a narrow pulse with a large peak value, and is continuously displayed from top to bottom. Each line of the screen is strobed, and at the same time, a pulse signal indicating graphic or text information is sent to each column, and the above operations are repeated, and various graphic or text information can be displayed.