The led unit board is used very much in the display screen. We also know that no matter what it is, there will be some problems after using it for a long time. How much do you know about the maintenance of the led unit board? In this article, Winbond Ying Optoelectronics summarizes the common failures and maintenance solutions of LED unit boards, and share them with you here!
Full color led display
One, the whole board of the led unit board does not light up
The whole board of the led unit board is not high. At this time, check whether the power supply of the led unit board is connected to the signal line for any problems, and then check the test card of the led unit board. The red light of the test card added to the led unit board flashes, it means that the test card is normal, otherwise it means the contact is poor. Then confirm that the 74HC245 of the led unit board is not short-circuited.
Second, the screen overlap of the led display
At this time, check the A, B, C, D signal input ports of the led unit board, whether there is a disconnection or short circuit between the test port and the 245, and determine whether the A, B, C, D signal output of the led unit board is normal.
Three, all or part of it is not bright
If the led display is all on or part of it is not on, then it is necessary to check whether the circuit between led unit boards 138 to 4953 is poorly connected or short-circuited.
4. When working, there is a single point or multiple points that are not lit
First, you need to find the control pin corresponding to the led unit board, and replace the led unit board or indicator light.
Five, when scanning, there are several or more lights
Check whether the A, B, C, and D signals of the led unit board are short-circuited, and whether the 4953 output terminal is in poor contact.
Six, one or several columns do not light up during work
Find the points that control the corresponding pin column on the led unit board, and then measure these points to check whether the output terminal of the driver IC (74HC595/TB62726) of the led unit board is connected properly.
Seven, display lack of color
When the display lacks color, the data terminal of the color of the led unit board needs to be detected to determine whether the connection data of the data signal of the color output terminal of the led unit board is normal.
Eight, display confusion
Display disorder is mainly the problem of the output terminal. It is necessary to check whether the latch terminal of the output terminal is connected successfully on the led unit board, or whether the signal at the output terminal of the led unit board is short-circuited.
