How to check and prevent the short-circuited of PCB circuit board

1. If it is manual welding, to develop good habits, first of all, before welding to visual inspection over the PCB board, and use multimeter check key circuit (especially power and ground) is short; secondly, each welding finished a chip with Multimeter measuring about whether the power and ground short circuit; in addition, welding not disorderly jilt iron. If the solder thrown on a chip welding foot (especially surface mount component), is not easy to find.

2 on the computer to open the PCB diagram, lit a short circuit of the network, to see where the nearest, the most likely to be connected to a piece of. Particular attention should be paid to the IC internal short circuit.

3 found a short circuit phenomenon. Take a piece of board to secant (especially for single / double plate after each part of secant function blocks are energized, part of exclusion.

4. Use short position analyzer, such as Singapore PROTEQ CB2000 short-circuit tracker, Hong Kong Lingzhi technology QT50 short-circuit tracker, British polar ToneOhm950 multilayer board road short-circuit detector etc..

5 small size of the surface mount capacitors must be careful, especially the power filter capacitors (103 or 104), a large number, it is easy to cause power supply and short circuit. Of course, sometimes bad luck, will encounter the capacitor itself is a short circuit, so the best way is to detect the capacitance before welding.if the BGA chip, since all solder joints is chip covered invisible and multilayer (more than 4 layers), so it is best in the design of each chip of the power split open, connected by magnetic beads or 0 ohm resistor, so there power earthing and short circuit, disconnect the magnetic beads were used to detect, very easy to locate to a chip. As BGA welding is difficult, if not the machine automatic welding, a little attention will be adjacent to the power supply and the two short circuit.


(Source: Inside information)