I believe that many people have used led display products, and even some people have a good understanding of led display. We are all familiar with the word "drive". If an electronic product wants to run normally, it must have a drive, such as our common computers. Led display is no exception. Today, I would like to talk with you about the driver of LED display.
Generally, LED full-color display driver chips are classified into the following two types:
1. Universal chip
It is widely used in the production of low-end LED screen. The most commonly used general-purpose chip is 74HC595, which has the functions of 8-bit latch, serial parallel shift memory and tri state output. Each circuit can output a maximum current of 35 mA (not a constant current).

2. Special chip
One of the biggest characteristics of the special chip is to supply a constant current source. Because LED full-color display screen is a current characteristic device, that is, under the premise of saturated conduction, its brightness changes with the change of the current size, not with the change of the voltage at its two ends. Constant current source can ensure the stable driving of LED and eliminate the flashing phenomenon of LED.
The two methods have their own advantages. How to choose? We should consider comprehensively according to our own needs, capital costs, etc!
Advantages/disadvantages of LED full color screen dynamic drive:
The advantage is that the display drive circuit is simple, and two ICs can drive eight LEDs below 10 ", which is low in cost. LEDs of various sizes can be directly connected to the main control board, driver board, and expansion board, or even can not use a PCB board. The power consumption is low. The time-sharing scanning display mode is used, and the power consumption is only 1/5 of the static display.
The disadvantage is that there are many connections between the LED and the drive board (8+LEDs in total). When there are many digits, the connection and maintenance are inconvenient.
Advantages/disadvantages of LED full color screen static drive:
The advantage is that the wiring between LED display components is very simple, and all LEDs can be connected in series with only 5-6 wires, which is convenient for debugging and maintenance. The display brightness is good, and the LED below 2m can be driven by appropriate driving elements, which is suitable for making large outdoor digital screens.
The disadvantage is that each LED needs 1-2 driving ICs, and the display component PCB needs to be made. The power consumption is slightly higher (5 times that of the scan driver). The cost is slightly higher (the average cost of each display driver is 0.4-1 yuan higher than that of the scan driver)