What are the methods for testing circuit boards? Jie Duobang teaches you how to detect circuit boards

The circuit board inspection principle and the computer inspection principle are almost the first look and then the test, the easy first and then the difficult. What are the methods to detect PCB circuit boards? Please read on.　　First: Perform visual inspection to understand the failure phenomenon through visual inspection. Understanding the failure phenomenon helps to analyze the failure in the next step. The analysis process includes asking, seeing, smelling, and testing. The question is to ask the user about the failure phenomenon, whether it is caused by improper use or a sudden failure during normal operation, and also to ask whether the circuit board has been repaired by others before and which components have been moved.　　 Second: Look at the electronic components carefully to see if there are obvious signs of discoloration, scorching, and whether there is a phenomenon such as false soldering or reverse soldering. You can use a magnifying glass to observe if necessary.　　 Third: Smell, smell for any peculiar smell, once integrated circuits (especially high-power devices) are burned out, they will smell of rotten eggs.　　Fourth: Measuring is measuring, and analyzing and finding faulty devices through measurement. Measurements are divided into static measurement (ie, measuring circuit board without power-on) and power-on measurement.