Many people do not know the specific reasons for the failure of the LED display module chip. This situation is actually not uncommon in LED display products. The most common situation is that the driving chip or constant voltage driving chip of the entire LED display module will be burned by smoking at the same time, or individual row driving tube chips will be burned. So what are the reasons for this situation? Regarding the cause of this situation, LED display manufacturer Lianchengfa has the following reasons:

1. The positive and negative poles of the power supply of the display screen are reversed

Normal LED display products, there will be VCC and GND signs at the power terminal position, or "+" and "-" signs, these two signs respectively represent the positive and negative wiring positions. However, operators who lack the basic knowledge of electrical engineering and electronics are still likely to inadvertently reverse the positive and negative poles of the power supply. Even qualified technicians may make operational mistakes. If the positive and negative poles of the power supply are reversed, most of the constant voltage drive chips on the module will be severely damaged or even burned by smoking.

2. The module is abnormal and the line height is always on

It is very common for the LED display to show one line of dark and one line of constant light and highlight, most of which are caused by abnormal cable contact or error in debugging parameters. In general, a well-designed LED display product will better avoid line-high-bright protection circuits. After the line height is abnormally bright, if it is not eliminated in time, the line driver chip of the module will be burned and destroyed due to continuous high current operation and sharp rise in temperature. Of course, if compared with previous cases, the current industry LED display module, the on-board power consumption of the row driver chip will be relatively low, and the maximum operating current of most row driver chips will not exceed 4A. The possibility that the line driver chip will smoke and burn due to the line constant light is relatively small.

3. The power supply voltage of the LED module is too large

Normally, the rated working voltage of the LED display module is 4V-6V, and the maximum limit working voltage of the integrated chip on the module will not be higher than 8V under normal circumstances, and the maximum reverse voltage of the LED tube is also below 8V. Therefore, the power supply voltage above 8V will definitely damage the integrated chip and the LED tube. When the voltage exceeds about 8V, the conventional constant voltage drive chip will start to heat up rapidly and is very likely to smoke and burn. Under normal circumstances, when the voltage exceeds 10-11V, the chip will be burnt to varying degrees if the power is continuously turned on for about 2 seconds. Since the output voltage of the LED display is a 5V constant voltage switching power supply, the possibility of overvoltage will not be very large. Even if the control circuit of the switching power supply fails, the possibility that its output voltage is abnormal and reaches 9V or more is very small. Therefore, in the process of our actual application, the most common cause of chip smoking and burning is that the positive and negative poles are reversed, the second is the abnormality of the module, and the second is the excessive voltage.