The led unit board is used very much in the display screen. We also know that no matter what it is, some problems will occur after long use. How much do you know about the maintenance of the led unit board? In this article, Winbond Ying Optoelectronics summarizes the common faults and maintenance solutions of the led unit board, and share it with you here!

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 is bad contact. 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 screen is all on or part of it is not on, then it is necessary to check whether the line between the led unit boards 138 to 4953 is poorly connected or short-circuited.

   4. When working, one or more points 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 has poor contact.

   Six, one or several columns are not bright at 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, it is necessary to detect the data terminal of the color of the led unit board 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 a 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.