Electronic circuit fault type

Through the above introduction, we to the electronic circuit fault causes have a preliminary understanding, at the same time we must also discusses the common failure types of electronic circuit, so as to better provide reference for electronic circuit troubleshooting. 

 

The type of failure caused by electronic circuit is the failure of the performance of electronic components such as transistor, capacitor and resistance. Malfunction caused by the contact of the circuit in the electronic circuit. The type of electronic circuit fault caused by external cause is: the technical personnel used electronic circuit not to follow the instructions to operate; Maintenance of technical personnel maintenance procedure is not standardized and unscientific. 

 

It is important to note that electronic circuits are different from other devices, and are subject to multiple failures due to external interference. The so-called interference refers to the external factors of the useful signals in electronic circuits that produce the disturbance, the stability of electronic circuit current is greatly reduced, under the influence of some components in the high and low current easy to damage. 

 

Therefore, to strengthen the research of the interference source of electronic circuit, the relevant measures can be taken to keep it away from interference, so that the electronic components can keep the best performance. Overall interference sources are divided into the following several types: (1) grounding unreasonable interference caused by the single power supply circuit, is usually the opposite electrode as its potential reference point, if using normal polarity power supply to the power supply, the power of the cathode is potential reference point. If the negative electrode power supply is used, the reference point of the potential is positive. If it is a bipolar power supply, the potential reference point is a positive and negative series node. In order to prevent interference in electronic circuits, the grounding element in the circuit is usually connected to the status reference point of the power supply. In addition, in order to avoid the interference of digital signal to analog signal, the digital signal and the analog signal should be set separately, and then converge on the selected point. If the position reference point grounding is handled improperly or the grounding resistance is too large, the ground electrical potential noise will be generated and the normal work of the circuit will be affected. 

 

(2) the inefficiency of the dc power supply filter ripple voltage used in the electronics work, usually consists of 50 hz alternating current (ac) after filtering, rectifier, voltage transformation and come, if the working process of the electronic circuit of ripple voltage increases suddenly, will bring interference to the circuit, the interference usually have rules to follow, therefore, in order to avoid the interference, should choose low noise, low output impedance of the power supply, can also be added in the circuit and the amplifier power filtering capacitance. 

 

(3) interference sources induced by induction can attach interference signals to the circuit through inductance and distributed capacitance, so that the electronic circuit can have a parasitic oscillation. In order to avoid such interference, on the one hand, can use shielding measures, the shielding shell connects to the earth, suppress electromagnetic interference in the transmission of the space, and cut off the jamming signal pathway. On the other hand, for the parasitic oscillation, the resistance capacitance network can be accessed at the suitable location of the electronic circuit.