LED display ordinary maintenance methods and steps

Author: From: Time: 2020-01-09

LED display ordinary maintenance methods and steps

The LED display display problems are also ever-changing, so it is not good to discuss in detail which problem, so let's talk about the detection method and the basic process of repairing the full color LED display. If this can be grasped, I want led to present the situation at a critical moment. You can check the reasons from these points and deal with the problem.

First, the detection method of LED display repairThere are detection methods for LED display repair, short circuit detection method, resistance detection method, voltage detection method, and voltage drop detection method, so let's talk about these methods in detail.

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 1. Short-circuit detection method, adjust the multimeter to the short-circuit detection block (generally with an alarm function, such as the announcement of a tweet), check whether there is a short-circuit phenomenon, and immediately deal with it after finding a short-circuit. Disadvantages of the display module. Some can be found by observing the IC pins and pin pins. Short circuit detection should be performed with the power to the circuit to avoid damaging the multimeter. This method is the most commonly used method, simple and efficient. 90% of the shortcomings can be detected by this method.

2. Resistance detection method, adjust the multimeter to the resistance level, detect the resistance value of a certain circuit board to the ground, and then test the same point on another same circuit board to test whether the normal resistance value is different If they are different, then the scale of the problem is determined.

3. The voltage detection method, adjust the multimeter to the voltage range, detect the voltage to ground at a certain point of the circuit in question, and compare whether it is similar to the normal value, which can easily determine the scale of the problem.

4, the voltage drop detection method, the multimeter is adjusted to the diode voltage drop detection file, because all ICs are composed of a large number of basic unit components, but only miniaturized, so when there is a current period on one of its pins, There will be a voltage drop across the pins. Generally, the voltage drop on the same pin of the same type of IC is similar. According to the value of the voltage drop on the pin is better or worse, it must be operated when the circuit is powered off.

 
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Second, repair tools
1. Electric iron + 1 sniffer, several solder
2. One electric batch for quick disassembly of module or unit board
3. Computer + sending card for sending programs to receiving card
4, a multimeter, used to test the module or the unit board detailed disadvantages
5.One pair of tweezers, scissors and scissors
6. Receiving card + HUB board, used to observe the defects of the module or the unit board
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Third, the fundamental process of LED display repair
1. Determine the type of HUB board used by the module or unit board, so that the interface definition of the cable is the same
2. According to different types of modules or unit boards, send corresponding programs to the receiving card to ensure that the modules and unit boards flash under the correct program. This is the condition to find out the reasons for the defects. Generally, the type of the module or the unit board is printed on the PCB board.
3. Observe the module or unit board phenomenon and determine the preliminary shortcomings. For example, common blind lights, string dots, small squares, etc.
4. Use a multimeter to find out the shortcomings, mainly using the short-circuit detection method above to detect between the chip and the lamp pin.
5.Detect again