In this case,

PCB reverse technology in the study, the reverse principle diagram is based on anti-PCB file map or directly from the product in-kind description of the PCB circuit diagram, designed to illustrate the circuit board principle and work. Moreover, this circuit diagram is also used to analyze the functional characteristics of the product itself. In this case,

In the forward design, the general product development must first schematic design, and then according to the schematic diagram of PCB design. Schematic design is the basis of circuit design, and only in the design of the schematic can be based on the printed circuit board design and circuit simulation. In this case,

PCB schematics have a special role whether they are used to analyze circuit board principles and product operating characteristics in reverse engineering or to be reused as the basis and basis for PCB design in forward design. Moreover, in the product debugging, the maintenance and the improvement process plays the indispensable function, the reverse schematic diagram manufacture is the PCB copy board service item breakdown, only needs to provide the model or the PCB document, the specialized PCB copy board company can 100% accurate for you to derive the PCB template or PCB file schematic. In this case,

In this case,

Anti-schematic diagram and schematic design software

In this case,

Commonly used anti-schematic diagram and schematic design software Protel99SE, Cadence, Proteus, OrCAD and so on. Protel99SE is used in the Windows9X / 2000 / NT operating system under the EDA design software, the use of design library management mode, can be networked design, with strong data exchange capabilities and openness and 3D simulation, is a 32-bit design software , You can complete the circuit schematic design, printed circuit board design and programmable logic device design work, you can design 32 signal layers, 16 power - ground and 16 machining layer. In this case,

Cadence is the world's largest provider of electronic design technology, process solution services and design services. Cadence software covers the entire process of electronic design, including system-level design, functional verification, IC synthesis and placement and routing, analog, mixed-signal and RF IC design, fully custom integrated circuit design, IC physical verification, PCB design and hardware simulation modeling Wait. Proteus is the world's leading EDA tools (simulation software), from the schematic layout, code debugging to the microcontroller and the external circuit co-simulation, a key switch to the PCB design, truly from concept to product complete design. Is the world's only circuit simulation software, PCB design software and virtual simulation software, three-in-one design platform. In this case,

In this case,

Anti - Schematic Diagram Specification

In this case,

1. Reasonable division of functional areas

In a good PCB board schematic design of the reverse design, 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 arranged to function to divide the region in the reverse schematic diagram can be convenient and accurate basis. In this case,

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 this process, do not forget to skillfully use the components on the circuit board serial number, they can help you faster functional partition. In this case,

 

2. Find the reference part

The reference part can also be said to be at the beginning of the schematic drawing of the main components used in determining the basis of pieces, according to the benchmarks of these pins to draw, to a greater extent to ensure the accuracy of the schematic. In this case,

For engineers, the determination of the benchmark is not very complicated things, under normal circumstances, you can choose to play a major role in the circuit components as a reference, they are generally larger, more pins to facilitate the drawing, Such as integrated circuits, transformers, transistors, etc., can be used as a suitable benchmark. In this case,

 

3. The correct distinction between lines, a reasonable mapping of wiring

For the ground, power lines, signal line distinction, the same engineers need to have the power of knowledge, knowledge of circuit connections, PCB wiring 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.

 

4. Master the basic framework, drawing on the same schematic diagram For some of the basic electronic circuit frame composition and schematic drawing, engineers need to master, not only to be able to some simple, classic unit circuit of the basic composition of the form of direct mapping, but also Can form an integral frame of the electronic circuit. On the other hand, do not overlook the same type of electronic products in the schematic diagram has some similarity, engineers can learn from the accumulation of experience, fully draw on the same circuit diagram of the new product schematics backwards.

 

5. Check and optimize the schematic drawing is completed, but also through the testing and verification links to the PCB schematic design of the end of the reverse. PCB components sensitive parameters of the nominal value of the need to check the optimization, according to the 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.

 

Schematic design flow

1. Create a new schematic file

Before entering the Protel 99 SE / Schematic design system, first of all to conceive a good schematic, that must be aware of the design

Of the project which need to complete the circuit, and then use Protel 99 SE to draw the circuit schematic.

2. Set the working environment according to the complexity of the actual circuit to set the size of the drawings, grid size, type, cursor type and so on. In the circuit design process, the size of the drawings can be constantly adjusted, set the appropriate size of the drawings is to complete the schematic design of the first step.

3. Place the component Select the component from the component library, arrange it to the appropriate position on the drawing, define and set the component's name and package, and adjust the position of the component on the working plane according to the alignment between the components And modifications to make the schematic beautiful and easy to understand.

4. Schematic wiring According to the actual needs of the circuit, the use of SCH provides a variety of tools, instructions for routing, the work plane of the device with electrical significance of the wires, symbols connected to form a complete circuit schematic.

5. Create a network table After completing the above steps, you can see a complete schematic circuit, but to complete the circuit board design, you need to generate a network table file. Network table is an important link between the circuit board and circuit schematic.

6. Schematic electrical inspection. After completing the schematic routing, you need to set the project options to compile the current project and modify the schematic using the error checking report provided by Protel 99 SE.

7. Compilation and Adjustment If the schematic has passed the electrical check, the schematic design is complete. This is for the general circuit design, especially the larger projects, usually require multiple modifications to the circuit to be able to pass the electrical inspection.

8. Save and report output Protel 99 SE provides various report tools (such as the network table, list of components, etc.), while the design of the schematic and a variety of reports to save and print output for the printing plate The circuit is designed to be ready.

Reverse schematic diagram and schematic design company in the country can also be engaged in anti-schematic diagram and schematic design of the company, only the reverse technology research company. Because in addition to their reverse research, in order to compete with the original design, we must also improve the schematic design capabilities. At the same time, schematic design in the reverse design of product debugging, maintenance and improvement process plays an indispensable role, therefore, as a professional PCB copy board company, must also have a strong anti-schematic diagram and schematic design capabilities.