LED Display Screen Short Circuit Detection and Resistance Detection Method

Publisher: Supplier of LED Display Time: 2022-01-20 16:11 Views: 725

The LED display screen is used in more and more occasions, and its environmental protection, high brightness, high definition, high reliability and other characteristics have been liked by everyone. However, compared with LCD splicing screens, the later maintenance of LED displays is more important. Let's talk about the short circuit detection method and resistance detection method of LED display. Before determining the cause of a problem with an LED display, first deal with the obvious problems, and then deal with some minor problems. The LED display with the screen shorted should be given priority.


1. LED display voltage drop detection method


It tunes the multimeter to the diode drop detection file. Since all ICs are made up of a lot of basic components, they're just tiny, so when current flows through a pin, there's a voltage drop across the pin. In general, the voltage drop of the same plug of the same type of integrated circuit is similar. Depending on the voltage drop value on the plug, it must be operated during a power outage. There are some limitations to this method. For example, if the device under test is high impedance, it cannot be detected.


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2. LED display manufacturers share resistance detection methods


Put the multimeter in the resistance gear, detect the LED to display the resistance value of a certain point of a circuit board to ground under normal conditions, and then detect whether the resistance value of the same point on another same circuit board is different from the normal resistance. If there is a discrepancy, determine the LED display problem area.


3. LED display short circuit detection method


Adjust the multimeter to the short-circuit detection block (either a diode voltage drop block or a resistance block, generally with an alarm function) to detect whether the LED display is short-circuited. When a short circuit occurs, it should be dealt with first to avoid burning other equipment. To avoid damage to the instrument, this method must be performed while the power is off.


4. Voltage detection method


Adjust the multimeter to the voltage level, and the LED display manufacturer checks the point-to-ground voltage in the circuit where the suspected LED display is faulty, and compares whether it is close to the normal value; otherwise, determine the scope of the problem with the LED display.


Note: Short circuit detection should be performed with the circuit powered off to avoid damage to the multimeter. This method is the most commonly used method, simple and efficient. Ninety percent of faults can be detected and judged by this method.


Let's talk about the resistance detection method. This method is to adjust the multimeter to the resistance gear, detect the resistance value of a certain point of a normal circuit board to ground, and then test the same point of another same circuit board to test whether the resistance value is different from the normal resistance value, if different The scope of the problem is then determined. Of course, the resistance value of the general circuit board is fixed, we only need to detect whether the resistance value of the circuit board to be detected is within the normal range, if it is higher than the normal range, or lower than the normal range, it needs to be replaced, or troubleshooting.