With the popularization and application of LED electronic display screens and LED full-color screens, LED display screens have become a beautiful landscape in today's information society. Especially at night, LED display screens are blooming and people can feel the world. Colorful and colorful. However, with the continuous expansion of the LED display applications, LED display problems have become more and more problems, then in the end how to test the LED display fault? Here's a brief introduction for everyone.

   1. The resistance detection method adjusts the multimeter to the resistance file, detects the resistance value of a certain point of a normal circuit board to the ground, and then detects whether the same point of the same circuit board is tested with the normal resistance value. If it is different then the scope of the problem is determined.

   2. The voltage detection method will adjust the multimeter to the voltage level and detect the voltage of the point where the circuit is suspected to have problems. Compare whether it is similar to the normal value, otherwise, determine the range of the problem.

   3, short-circuit detection method, the multimeter will be transferred to the short-circuit detection block (some diode downshift or resistance file, generally with alarm function), the detection of whether there is a short circuit phenomenon, found that short-circuit should be prioritized, so that it does not burn out Other devices. This method must be operated with the circuit powered down to avoid damage to the watch.

   4, pressure drop detection method, the multimeter to adjust the voltage drop detection diode, because all of the IC is composed of many basic units, but miniaturized, so when there is a current through a pin, There will be a voltage drop on the pin. Generally, the voltage drop on the same pin of the same type of IC is similar, and the voltage drop on the pin is better or worse, and the circuit must be operated with the power off. This method has certain limitations. For example, if the device under test is high-impedance, it cannot be detected.