Four Major Methods of Fault Testing for LED Display Screen
First, a resistance detection method, the multimeter to detect a resistance profile, a normal circuit board to ground resistance value, and then detect the same point another piece of the same circuit board test and normal resistance values are different, if different from the scope of the problem.
Two, voltage detection method, the multimeter is transferred to voltage files, to detect the voltage to a certain point of the circuit with doubting questions, whether it is similar to the normal value, otherwise, it determines the scope of the problem.
Three, short-circuit detection method, the multimeter transferred to the short-circuit detection gear (some diodes voltage drop or resistance files, generally has alarm function), detect whether there is short circuit phenomenon, found that after short circuit, we should first solve, so that it does not burn other devices. This method must be operated in the case of circuit breaking down to avoid damage to the table.
Four, the pressure drop detection method, the multimeter transferred to the diode voltage drop detection file, because all IC is composed of a number of basic single components, is only miniaturized, so when there is a current on its pin, there will be voltage drop on the pin. The pressure drop of the same type of IC is similar to that of the same type. According to the pressure drop value on the pin, it is necessary to operate the circuit when the circuit is broken. The method has some limitations, such as the detected device is high resistance, and it is not detected.
