PCB News - PCB circuit board chip electronic devices

PCB circuit board chip electronic devices

With the continuous development trend of electronic equipment, the development trend of PCB circuit boards has become more and more demanding. PCB circuit boards have just begun to develop in a difficult and difficult direction with high density. In the case of application, customers will It is necessary to plug holes when mounting electronic devices. This is why, in fact, the key to plug holes is for this reason:

1. Avoid the short-circuit failure caused by the tin from the buried guide hole and the component surface when the PCB passes through the wave soldering machine; especially when you put the pad on the BGA pad, you must first make the plug hole, and then electroplating gold treatment, which is beneficial Electric welding of BGA.

2. After the assembly of the surface layer of the electronics factory and its components is realized, the PCB must be vacuumed on the testing machine to form a negative pressure before it can be realized:

3. Avoid surface solder paste flowing into the hole to cause false soldering and affect the PCB circuit board patch;

4. Avoid the solder balls popping up when the wave soldering machine is used, which may cause short circuit failure of the PCB circuit board;

5. Avoid flux residue in the buried guide hole.

Ways to quickly detect common failure phenomena of PCB circuit boards

PCB circuit board is not a simple step-by-step to make a wooden board, just drill a hole and punch the electronic device. The manufacture of PCB circuit boards is not too difficult, and the difficulty depends on the inspection of common faults after the manufacture is carried out. Whether it is a favorite or a technical engineer in the manufacturing industry, it is a headache for the PCB circuit board to encounter the phenomenon when the PCB circuit board is adjusted, just like the programmer encounters a BUG.

PCB circuit boards Some people have a deep interest in adjusting PCB circuit boards. PCB circuit boards are like a programmer dealing with bugs. There are many common PCB circuit boards and many PCB circuit boards, except for power supply design., The destruction of electronic components, line short-circuit faults, the quality of electronic devices, PCB circuit board PCB circuit board disconnection common faults are not rare. Common PCB circuit boards. The key to common failures of PCB circuit boards or are concentrated on electronic devices, such as capacitors, resistors, inductors, diodes, tertiary tubes, field effect tubes, etc., integrated IC and crystal oscillator circuits Significant damage, and an immediate way to distinguish common faults of such electronic devices can be observed with both eyes. Significant burn marks on the surface of electronic components that have been significantly damaged. For common faults of this kind, immediately dismantle the phenomenon components and replace them with new ones.

Perhaps, not all the destruction of electronic components can be detected by human eyes, such as the resistors, capacitors, secondary and tertiary transistors mentioned above. Under certain conditions, the destruction cannot be seen from the surface and must be relied on. Technical and professional inspection tools are used for maintenance. Common inspection tools include: digital multimeters, capacitor meters, etc., when it is verified that the working voltage or current of an electronic component is not within the normal range, it indicates that the electronic device or the previous electronic device If there is a problem with the device, please replace it immediately and check to see if it is normal. When the electronic device is damaged, it can be inspected whether it is inspected with two eyes or inspected with an instrument. However, sometimes when we give the electronic device on the PCB circuit board, we will encounter the phenomenon that the inspection can not be found, but The PCB circuit board cannot work under normal conditions.

Many beginners have no choice but to replant wood or buy seeds when they encounter this kind of phenomenon. In fact, when encountering this kind of situation, in many cases, during the whole installation process of electronic devices, due to the phenomenon that each electronic device cooperates with each other, the characteristics may be unstable. In such situations, instruments and equipment can no longer provide assistance. You can try to distinguish the scope of common faults based on the current intensity, and make them as small as possible. Technical engineers with work experience may be able to quickly identify common fault areas. However, it is not 100% clear which of the actual electronic devices is broken. The only way is to try to disassemble and replace abnormal components until the phenomenon components are found. In previous years, my server mainboard seepage, and when I was overhauled by professionals, I also encountered common faults that were not detected. In the whole process of overhaul, I had to dismantle and replace several components, namely, the power supply system integrated IC and the second Level tube, UsB battery charging components (it is the blue jack of the notebook computer, which can charge the battery of the machine and equipment in standby mode). Finally, it is also based on inspections and inspections to replace abnormal integrated ICs, and finally it is clear that it is The components next to the pci card are short-circuited.

It’s often said that all of them are actually electronic components. Perhaps, even if the PCB circuit board is the focus of the electronic device, then the common faults of the PCB circuit board will undoubtedly appear. A very simple example is Due to the processing technology, the dead electroplating position may be disconnected during the entire etching process of the PCB circuit board. In such a situation, if it is not possible to make up the wire, then only use the thin copper wire aj23 to deal with it. The common faults of PCB circuit boards are indeed very inconvenient when they are not significantly destroyed. In the whole process of the inventory, there will be a kind of concentration and spirit. After the phenomenon is found, there will be an inexplicable sense of satisfaction. It is this kind of emotion that programmers deal with bugs. I am often interested in checking out certain boards that cannot be repaired. I think that is a kind of happiness.