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Several important elements in the later check of PCB designnewlisttop
Several important elements in the later check of PCB design
When the routing in finished on one PCB Prototyping board and there is no error in both the connecting and th...
Why does poor tin welding always occur in PCB
Why does poor tin welding always occur in PCB
In the process of PCB Prototype design and production, do you usually meet the problems that poor tin welding...
Maintenance of PCB dividing board
Maintenance of PCB dividing board
1.The reasons for the operational problems occurring to PCB Prototyping dividing boards: When the storage bat...
The common malfunctions and the treatments of PCB sub-machine
The common malfunctions and the treatments of PCB sub-machine
1.If the indicator light is off when the switch in opened: one possible reason is the fuse wire is fused and n...
An analysis on the design method and main points of PCB chart
An analysis on the design method and main points of PCB chart
In PCB design, the following points need to be paid special attention:1.Routing direction: Seen from the weldi...
Five major trends in terms of PCB technology development
Five major trends in terms of PCB technology development
More and more electronic equipments are going high-performance, high-speed, light and thin. As a multi-discipl...
The design principle of single chip control board in PCB design
The design principle of single chip control board in PCB design
1.Layout of electronic components When laying out electronic components, relevant components should be put clo...
Reservation and validity period of PCB
Reservation and validity period of PCB
After passing the finished goods inspection, PCB will be packed with vacuum package to be shipped. Why does PC...
Differences between the positive layer and negative layer on the PCB
Differences between the positive layer and negative layer on the PCB
Negative layer on the PCB: Generally, we mean tenting processing, in which acid chemical liquid is used for et...
How to reduce mistakes in PCB design and improve efficiency?
How to reduce mistakes in PCB design and improve efficiency?
Circuit board design is a key and time-consuming task. Whenever problems arise, engineers need to inspect the ...

How to analyze where the problems lie when the PCB loses its efficiency?

August 6, 2018

PCB Image:How to analyze where the problems lie when the PCB loses its efficiency?

To figure out the accurate reasons or mechanisms why PCB loses the efficiency or is defective, we must follow the basic principle and analysis procedure, or important information may be omitted, which makes it impossible to continue to conclude the reasons for the mistakes or even the possibility. Generally, the basic procedures must be firstly based on efficiency failure to figure out the mode and place of efficiency failure, namely, failure location or malfunction location by collecting information, testing functions, electric performance test or some simple appearance inspection. For some simplified Cheap PCB Manufacturing or PCBA, it is very easy to locate the place of efficiency failure, whereas, for complex BGA or components or boards enclosed with MCM, defects are not easy to be observed by microscope. When this occurs, other aids may be adopted to figure it out. The next step is to make an analysis of the efficiency failure, that is, to make an analysis of the reasons for efficiency failure or mechanisms for defects in PCB with the aid of various chemical or physical methods., such as, insufficient welding, pollution, mechanical damage, moisture stress, medium corrosion, fatigue damage, CAF or particle transferring, over stress, etc..

The next step is an analysis of the reasons for efficiency failure, namely, the analysis of mechanism of efficiency failure and processing procedure. There are many reasons which cause the efficiency failure, so it is necessary to conduct some necessary experimental verification. Generally speaking, you should do everything you can to conduct experimental verification to figure out the accurate reasons for the failure, which will provide a definite base for the improvement in the next step. The final step is prepare the analysis report for efficiency failure in which facts are clearly stated, logic reasoning is rigorous and the content is well organized with no imagination based on the experimental data, fact or conclusions.

In the course of analysis, make sure that analysis should be from simple to complex, from the outside to inside, from no damaging samples to using damaged samples. Only in this way can it avoid losing key information or introducing new man-made failure mechanism. Just as in an traffic accident, if the party who destroys or runs away from the accident scene, it will be difficult for the police to define responsibility however skilled the police are. At this time, the party who destroys or run away from the scene shall undertake full responsibility according to traffic regulations, which is the same in the case of PCB or PCBA. No analysis is possible once the failure scene is destroyed and the real failure reasons will never be figured out once the circumstances of the failure scene are destroyed or damaged, especially when the failure samples are limited.