The importance of the electronic components surrounding integrated circuits

Troubleshooting and repairing electronic equipment can really make us feel great satisfaction every time a problem is solved. It doesn’t matter how many hours you’ve put in, especially if you’re a beginner and your only goal is to find the fault and get your computer working again. What you want is experience and the fun of learning new things as you go deeper into electronic repair. But some of us as electronic troubleshooters give up easily if we run into problems that are difficult to solve, maybe you don’t understand how the circuit works and I myself was in this situation before. Don’t worry if you don’t understand how a particular circuit works as you continue reading. I will provide you with a solution.

Typically, a repair technician or engineer has a procedure or his or her own style of repairing equipment. I can say that most of us as electronic repairmen do a test first to see what the fault is before we start to open the equipment and repair it. For example, a monitor with a bright white horizontal line across the screen tells us that the fault is in the vertical section or circuit. Once the cover is opened, we will go directly to the vertical section and look for dry joints, perform voltage tests, check related components, test the vertical yoke coil, and even directly replace the vertical IC.

This is a normal procedure for those who are highly experienced in electronic repair and really understand how a particular circuit works. What if you are new to this repair field or don’t really understand how the circuit works? So how are you going to solve the problem? Easy! Just directly replace the suspected IC section and check all surrounding components. Let me put it in a better picture. A color problem usually related to a monitor’s color card. If you don’t understand how a color circuit works, it doesn’t matter, what you need to do is just directly replace the color IC (usually the board will have two ICs, one is the video preamp and the other is the driver IC video) and retest the monitor. If the Monitor works fine, then your problem is solved. However, if the problem persists, you should use another method that checks all the surrounding components.

You would not believe that many times the IC is not at fault and the real culprit was the surrounding components such as a ceramic capacitor, diode, or even a shorted transistor. Two weeks ago, I came across an LCD monitor that would turn off after a few seconds. After some checking, I confirmed that it was the faulty inverter board. It is a small board with many SMD components except for the high voltage transformers and electrolytic capacitor pairs. The inverter IC is also an SMD and I don’t have this part. I proceed to check the surrounding components first before deciding to order the inverter IC online. Do you know what I found? I found a shorted SMD capacitor somewhere near the inverter IC. The value was 0.15 microfarads and a new capacitor brought the LCD monitor back to life.

Another case, it was a 15″ monitor made in China, the high voltage went up to 15KV and turned off after testing it with a high voltage probe. I suspect the horizontal circuit is causing the problem, but a new h/v oscillator (TDA4857PS IC ) won’t help either.Next I just salt all the surrounding components (components only related to the horizontal pin) and check one by one and found that one of the resistors has increased in resistance.I have the option to start tracing from the pins of the IC but I found that I removed all the surrounding components and tested which one is faster.

This method can also be used if you cannot find any data for a particular IC, for example a new model of equipment on the market. As mentioned above, it need not always be IC’s fault. However, if you have confirmed that all the surrounding components have been tested ok, then there is a good chance that the IC is indeed faulty. This is true only if you are really sure that the circuit is the cause of the problem. In other words, you wouldn’t replace the H/V oscillator IC when there’s a color problem, would you?

While you can repair electronic equipment by checking all of the surrounding components, I actually encourage you to learn beyond that, such as voltage and signal tracing, as these methods can really speed up your repair work. You must also learn to read a schematic diagram. I want you to know that some problems cannot be solved just by checking the surrounding components. For example, if the h/v oscillator IC did not send a signal to the gate pin of B+ FET, the screen will become small (small width). Now if you check all the surrounding components in the B+ circuit, I’m sure you won’t find any faulty components because the problem is in the h/v oscillator IC and this IC is located a bit far from the B+ circuit. You will waste your time and the problem cannot be solved!

Conclusion: This article acts as a guide to help you use the surrounding component check method on any type of equipment you want to repair, including boards that use many SMD ICs. Your basic skill in electronics and testing should be solid; otherwise a faulty component might think it’s good, and in the end you won’t be able to detect the fault. Keep learning and improving and I believe that one day you will achieve what you want to be. All the best to you!

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