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How to check whether the printed circuit board is short circuit?

How to check whether the printed circuit board is short circuit?

In the process of printed circuit boards, if not careful, it is easy to let the printed circuit boards appear problems, circuit boards once short-circuited, for human safety is a great hidden danger, but also may burn out components, serious will directly cause the entire circuit board scrap. Therefore, for circuit board short circuit problem, we need to focus on inspection. How to check whether the printed circuit board is short circuited? FASTPCBA technician answers for you:

1. Open the PCB chart on the computer, light up the short-circuit network, see where the nearest, most easily connected to a piece. Special attention should be paid to the internal short circuit of IC.

2, use short-circuit positioning analyzer equipment for inspection. Or by increasing the current to check, the use of low-voltage high current, 5V below, 3-5A high current, where the heating indicates that there may be a short circuit.

3, if artificial welding, you need to be careful. First, check the PCB board visually before welding, and use a multimeter to check whether the key circuits (especially the power supply and ground) are short-circuited. Do not fling soldering iron randomly during the welding process, if the solder flings to the chip solder foot (especially the surface mount component), it is not easy to find. In addition, every time you finish welding a chip, use the multimeter to check whether the power supply and the ground are short circuited.

4. Small size surface mount capacitor welding must be careful, especially the power filter capacitor (103 or 104), a large number, it is easy to cause power and ground short circuit. Another case is that the capacitor itself is short-circuited, so the best way is to test the capacitor before welding.

5. If there is a BGA chip, because all solder joints are covered by the chip can not be seen, and is a multi-layer board (more than 4 layers), so it is best to design each chip power split, with a magnetic bead or 0 Euro resistance connection, such a power supply and ground short circuit, disconnect the bead detection, it is easy to locate a chip. Because of the difficulty of BGA welding, if it is not automatic welding machine, a little negligence will be adjacent to the power supply and two short-circuit welding balls.

6. if there is a short-circuit phenomenon. Can take a board to cut the line (especially suitable for single/double-deck board), cut the line will be each part of the functional block respectively electrified, one by one to eliminate.

The above is how to check whether the PCB circuit board is short circuited. PCB circuit boards are most likely to cause short circuit in the pin-dense IC, USB socket, VCC and GND pin connected to other devices, in the inspection of the need to focus on these places.