The Daily Maintenance Method Of Full Color LED Display
Mar 31, 2021
Before LED display maintenance, you need to prepare multimeter, electric iron, blade, tweezers and other tools. In the detection of LED display fault problems, we must deal with it in the way of primary and secondary. The obviously serious problems should be dealt with first, and the problems that are not very serious should be dealt with later. The short circuit problem belongs to the highest priority and must be dealt with immediately. There are several methods in the process of maintenance
1. Observation method
Through naked eye observation, open circuit is one of the problems often found in observation methods. It can be seen by eyes. For example, the PCB circuit is broken due to scratching, or the open circuit is caused by accidental breaking of an electric drill.
2. Contrast method
We can't seel whether the IC is burnt out with the naked eye, but we can replace it with a good IC; if the signal does not remember whether it was originally connected, we can use the unit board to measure the corresponding position to judge. The contrast method is often used in the repair process. It is very important to master this method. It allows you to quickly find out where the fault is.
3. Elimination method
A failure of the full-color LED display may be caused by a variety of reasons. We need to accurately determine each cause of the display failure, and then deal with it one by one, but it must be noted that it must be processed according to the priority level.
4. Resistance detection method
Set the multimeter to the resistance range, check the resistance value of a certain point of a normal circuit board, and then check the same point of another same circuit board to test whether the resistance value is different from the normal resistance value, if it is different, it is determined the scope of the problem.
5. Voltage detection method
Adjust the multimeter to the voltage range, check the voltage to ground at a certain point of the circuit suspected to have a problem, and compare whether it is similar to the normal value, otherwise the fault range of the display screen problem will be determined.
6. Short circuit detection method
Set the multimeter to the short-circuit detection block to detect whether there is a short-circuit phenomenon in the LED display. After a short-circuit is found, it must be solved first to ensure that other devices are not burned out. Note: The short-circuit detection method must be operated when the circuit is powered off to avoid damage to the meter.
7. Pressure drop detection method
Adjust the multimeter to the diode voltage drop detection gear, because all ICs are composed of many basic single components, but are miniaturized, so when there is a current passing through one of its pins, there will be a voltage on the pin. drop. Generally, the voltage drop on the same pin of the same type of IC is similar, and it is better or worse according to the voltage drop value on the pin. Note: The voltage drop detection method must be operated when the circuit is powered off. This method has certain limitations. For example, if the tested device is high-impedance, it cannot be detected.
There are three main reasons for the failure of full-color LED display: open circuit, short circuit, and IC damage. If it is an open circuit, connect the interrupted signal line to solve the problem; if it is a short circuit, we only need to deal with the short circuit. The last problem is that the IC is damaged. There is nothing to say about it. If it is broken, replace it with a new one. Just fine.
