6 ways to detect short circuits on PCBboards?

First,Open the PCB design on the computer, light up the network of short circuits andsee what is closest and easiest to connect to a piece. Pay special attention tothe IC internal short circuit.

Second,if you are manually soldering, good habits should be developed to.

1,visually check the PCB board once before soldering and use a multimeter tocheck if the key circuits (especially power and ground) are short-circuited.

2,each time after welding a chip with a multimeter to test whether the powersupply and ground short-circuit.

3, donot fling the soldering iron indiscriminately when soldering, if the solder isflung onto the solder pins of the chip (especially the surface-mountedcomponents), it will not be easy to check.

Third,found to have a short circuit phenomenon. Take a board to cut the line(especially suitable for single/double board), after cutting the line, eachpart of the functional block will be separately energised, and graduallyeliminate.

Fourth,Use short circuit locating analysis instrument

Fifth,If there is a BGA chip, as all the solder joints are covered by the chipinvisible, and it is a multi-layer board (more than 4 layers), so it is best todivide the power supply of each chip during design and connect it with magneticbeads or 0 ohm resistors, so that when there is a short circuit between thepower supply and the ground, disconnect the magnetic beads to detect it and itis easy to locate a certain chip. As BGA is difficult to weld, if it is notautomatically welded by machine, a little inattention will short-circuit theadjacent power and ground two solder balls.

Sixth,small size SMD capacitors must be soldered with care, especially the powersupply filter capacitor (103 or 104), the large number of which can easilycause a short circuit between power and ground. Of course, sometimes it is badluck to come across capacitors that are short-circuited themselves, so the bestway is to test the capacitors once before soldering.