Technical Library | 2015-07-14 21:32:04.0
The PCB industry is ever changing and adapting to new technologies. OEM specifications and requirements have also advanced due to these technologies. In some cases the OEMs are asking for a low resistance test to be performed on some or all electrical test nets of the PCB or on the holes of the PCB. This requirement is typically not well defined on the fabrication drawing and that leads to misleading conclusions by the fabrication house (...) This paper will use the data gathered by the company’s operations to outline what a 4-wire Kelvin test is and how it can be used. Several examples will be illustrated of what the 4 wire Kelvin test can and cannot do. A clear definition of what limitations are present during the testing operation will be defined. The paper will assist designers in understanding how the low resistance test can assist them and also identify causes that can identify unwanted concerns/issues.
Technical Library | 2020-11-19 20:35:26.0
Simultaneously with the first complex electronic circuits, the task of creating effective means of diagnosing and repairing them appeared. In previous decades, specialized programmable stands were used for diagnostics of serial electronic products, as well as various testers and probes for troubleshooting during their operation. But the dramatic increase in the density / cost factor, in parallel with the very rapid modification of electronic products, made programmable stands economically ineffective even in mass production. The use of traditional laboratory equipment (oscilloscopes, multimeters, etc.) requires power supply to the defective modules, which is often impossible and unsafe, since it can lead to failure of the working modules of the module. In addition, the use of this equipment requires documentation and highly qualified personnel. More automated and sophisticated signature analysis systems came to the rescue in solving this problem. A feature of these devices is that they allow you to test digital and analog assemblies without dismantling components and without supplying voltage.
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