Zhimao curve PCB splitter shares: 6 major PCBA circuit board short circuit detection steps
1. Manual welding, first of all, you must develop a good habit, visually inspect the PCBA board before welding, and use a multimeter to check whether the key circuit (especially the power supply and ground) is short-circuited; secondly, use a multimeter to measure whether the power supply and ground are short-circuited every time a chip is welded; in addition, do not swing the soldering iron randomly during welding. If the solder is thrown onto the chip's solder pins (especially surface-mount components), it will not be easy to find.
2. Open the PCBA diagram on the computer, light up the short-circuited network, and see where it is closest and most likely to be connected together. Pay special attention to the internal short circuit of the IC.
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3. A short circuit is found. Take a board to cut the line (especially suitable for single/double-layer boards), and after cutting the line, power on each functional block separately, and eliminate them one by one.
4. Use a short circuit location analyzer, such as: Singapore PROTEQ CB2000 short circuit tracker, Hong Kong Lingzhi Technology QT50 short circuit tracker, British POLAR ToneOhm950 multilayer board short circuit detector, etc.
5. If there is a BGA chip, since all the solder joints are covered by the chip and cannot be seen, and it is a multilayer board (more than 4 layers), it is best to separate the power supply of each chip during design and connect it with a magnetic bead or 0 ohm resistor. In this way, when the power supply and ground are short-circuited, disconnect the magnetic bead detection and it is easy to locate a certain chip. Since BGA welding is difficult, if it is not automatically welded by a machine, the adjacent power supply and ground solder balls will be short-circuited if you are not careful.
6. Be careful when welding small-sized surface mount capacitors, especially power filter capacitors (103 or 104). There are many of them, which can easily cause a short circuit between the power supply and the ground. Of course, sometimes you are unlucky and encounter a capacitor that is short-circuited itself, so the best way is to test the capacitor before welding.
Copyright statement: This article was originally written by "Xiao Shijiang", a blogger of the Electronic Engineering Album, and edited by Xiaozhi, the Zhimao curved PCB splitter. The copyright belongs to the original author. The reprint is only for the dissemination and sharing of information and knowledge. This public account maintains a neutral attitude towards the views in the article. If there is any infringement, please contact Xiaozhi in the background to delete it.
