The Principle of Reverse Engineering in pcb Copy Board
Compared to pcb different design, pcb copy board is a reverse means of research, through a professional pcb reverse schematic diagram software and a series of reverse technology research, and derived product pcb files, bom list, sch schematic files, such as a full set of means of production , And then used in the process of product cloning.
Nexi in the years of the pcb copy board practice, has accumulated rich experience, mastery of the hundreds of anti-push mode, combined with the latest pcb reverse schematic software, can provide customers with a variety of high-frequency board mapping Schematic and modify the multi-layer blind buried orifice of the schematic diagram of the reverse design, anti-painted schematic diagram, 8-layer server computer motherboard schematic reverse design, more than 10 pcb file anti-drawing schematic diagram and so on. Then the problem is coming, reverse the process of drawing what the need to pay attention to the matter? Nexi summed up the experience:
First, the rational division of functional areas
In an intact pcb circuit board reverse design of the schematic diagram, a reasonable division of functional areas to help engineers reduce unnecessary trouble and improve the efficiency of rendering. In general, a pcb board features the same components will be focused on the layout of the functional division of the region can be reversed in the schematic diagram has convenient and accurate basis. However, the division of this functional area is not arbitrary. It requires engineers to have some knowledge of electronic circuit-related knowledge. First of all, to find a functional unit of the core components, and then follow the trace connection can follow the same function unit to find out the other components, the formation of a functional area. Functional partitioning is the basis of schematic drawing. In addition, in the functional partition process clever use of components on the circuit board serial number, is conducive to faster functional partition.
Second, find the benchmark
Fittings can be said to be at the beginning of the schematic drawing of the main components to be used in determining the basis of pieces, according to the benchmarks of these pins to draw, to the maximum extent possible to ensure the accuracy of the schematic. For engineers, the determination of the benchmark is not very complicated thing, under normal circumstances, you can choose to play a major role in the circuit components as a benchmark, they are generally larger, more pins to facilitate the drawing process, Such as integrated circuits, transformers, transistors, etc., can be used as a suitable benchmark.
Third, the correct distinction between lines, a reasonable mapping of wiring
For ground, power lines, signal line distinction, the same engineers need to have the power of knowledge, knowledge of circuit connections, pcb cabling knowledge and so on. The distinction between these lines, can be connected from the components, the width of the copper foil and the characteristics of electronic products and other aspects of their analysis. In the wiring drawing, in order to avoid line crossing and interspersed, the ground can be a lot of use of the ground symbol, a variety of lines can use different colors to ensure clear lines of different lines, a variety of components can also use special signs, or even The unit circuit separately drawn, and finally combined.
Fourth, master the basic framework, drawing on similar schematics
Engineers need to master the basic electronic circuit frame structure and schematic drawing method, not only to be able to some simple, classic unit circuit of the basic composition of the form of direct drawing, but also to form the overall framework of electronic circuits. In addition, the same type of electronic products in the schematic diagram has a certain degree of similarity, engineers can learn from the accumulation of experience, fully draw on the same circuit diagram to reverse the new product schematics.
Fifth, check and optimize
Schematic drawing is complete, but also through the testing and verification links can be said that the reverse design of pcb schematic end. On the pcb distribution parameters sensitive to the nominal value of the components need to be checked and optimized, according to pcb file map, the schematic contrast analysis and verification to ensure that the schematic diagram and the file map exactly the same. If in the check found in the layout of the schematic does not match the requirements, but also to conduct the schematic adjustment until it is completely reasonable and standardized, accurate and clear.