Rotating outdoor LED display is a new type of display that realizes graphic display by synchronously controlling the position and lighting state of light-emitting diodes. It has developed rapidly because of its novel structure, low cost, and 360° visual range. The core technology lies in the precise control of the synchronization between the position of the outdoor LED display and the light-emitting state.
There is only one row of display devices for the rotating outdoor LED display, and this row of outdoor LED displays is driven by the outdoor LED display with a constant speed to rotate. At the same time, the lighting state of the outdoor LED display is synchronously controlled by the control circuit to make the motor every Turning a certain angle, the display content of this column of outdoor LED display changes once, and there is a unique display content when rotated to any position, that is to say, the rotating outdoor LED display screen adopts column-by-column display and adopts The mechanical rotation is used to replace the scan display.
The principle of the rotating outdoor LED display is not complicated, and its hardware structure is relatively simple. However, to make the rotating outdoor LED display able to stably display the set image or text, three technical difficulties need to be overcome:
1. The rotating screen controls the power supply of the control circuit. When the system is working, the control circuit rotates with the rotor of the motor, so it is difficult to provide a stable power supply for the rotating control circuit and the outdoor LED display.
2. The rotating screen displays the smear problem horizontally. Because the rotating screen adopts a single-column outdoor LED display rotating scan to realize the cylindrical image display, this makes the image number display stick in the horizontal direction, forming a smear phenomenon.
3. Solve the lack of display brightness. Because the working principle of the rotating outdoor LED display electronic screen determines that compared with the ordinary flat outdoor LED display, the time to display each column is much less, so the brightness will be greatly reduced.
To make the designed rotating outdoor LED display have a better display effect, it is necessary to solve these three problems in the design. For the power supply of the rotating outdoor LED display, it is a relatively simple and reliable method to supply power to the system by contacting the brushes fixed on the base with the rotating metal guide rail or metal wheel shaft. The design of this article is to provide a constant 12V DC voltage through the brush, and then convert it into 2.5V, 3.3V, 5V and other voltages by the DC-DC chip to maintain the control system work.
To solve the horizontal smear of the rotating screen, it is mainly based on the characteristics of the rotating scan to insert a completely black time slot between the two columns of pixels, so that the stickiness of the two columns of image display points can be eliminated. To solve the problem of insufficient brightness display, the design of this article uses four columns of outdoor LED display lights to alternately display each pixel on each rotating screen without continuing to increase the brightness of the outdoor LED display lamp. Point, so that the brightness becomes four times the original under the condition of the same rotation rate.
