PCB News - You copy it or not copy it is there. PCB copy board detailed steps

The technical realization process of PCB copy board is simply to scan the circuit board to be copied, record the detailed component location, and then remove the components to make the bill of materials (BOM) and arrange the material purchase, and the empty board is The scanned picture is processed by the copy board software and restored to the PCB board drawing file, and then the PCB file is sent to the plate making factory to make the board. After the board is made, the purchased components are soldered to the made PCB board, and then the circuit board is tested And debugging.

The specific steps of PCB copy bo ard:

In one step, get a piece of PCB. First, record the model, parameters, and positions of all vital parts on paper, especially the direction of the diode, the tertiary tube, and the direction of the IC gap. It is easy to use a digital camera to take two photos of the location of vital parts. The current PCB circuit boards are getting more and more advanced. Some of the diode transistors on the above are not noticed at all.

The second step is to remove all the multi-layer boards and copy the boards, and remove the tin in the PAD hole. Clean the PCB with alcohol and put it into the scanner. When the scanner scans, you need to raise the scanned pixels slightly to get a clearer image. Then lightly polish the top and bottom layers with water gauze paper until the copper film is shiny, put them in the scanner, start PHOTOSHOP, and scan the two layers separately in color. Note that the PCB must be placed horizontally and vertically in the scanner, otherwise the scanned image cannot be used.

Three steps, adjust the contrast, brightness and darkness of the canvas, make the part with copper film and the part without copper film have a strong contrast, then turn the second image into black and white, check whether the lines are clear, if not, repeat this step. If it is clear, save the picture as black and white BMP format files TOP.BMP and BOT.BMP. If you find any problems with the graphics, you can also use PHOTOSHOP to repair and correct them.

Four steps, convert two BMP format files into PROTEL format files, and transfer two layers in PROTEL. For example, the positions of PAD and VIA after two layers basically coincide, indicating that the previous steps are well done. If there is Deviations, repeat three steps. Therefore, PCB copying is a work that requires patience, because a small problem will affect the quality and the degree of matching after copying.

Five steps, convert the BMP of the TOP layer to TOP.PCB, pay attention to the conversion to the SILK layer, which is the yellow layer, and then you can trace the line on the TOP layer, and place the device according to the two-step drawing. Delete the SILK layer after drawing. Keep repeating until all the layers are drawn.

Six steps, import TOP.PCB and BOT.PCB in PROTEL and combine them into one picture and it will be OK.

Seven steps, use a laser printer to print TOPLAYER and BOTTOMLAYER on transparent film (1:1 ratio), put the film on the PCB, and compare whether there is any error. If it is correct, you are done.

A copy board that is the same as the original board was born, but this is only half done. It is also necessary to test whether the electronic technical performance of the copy board is the same as the original board. If it is the same, it is really done.
Remarks: If it is a multilayer board, you need to carefully polish to the inner layer, and repeat the three to five steps of copying the board at the same time. Of course, the naming of the graphics is also different. It depends on the number of layers. Generally, double-sided board copying is more than The laminate is much simpler, and the multi-layer copy board is prone to misalignment. Therefore, the multi-layer board copy board must be especially careful and careful (the internal vias and non-vias are prone to problems).

Double-sided copy board method:

1. Scan the upper and lower layers of the circuit board and save two BMP pictures.

2. Open the copy board software Quickpcb2005, click "File" "Open Base Map" to open a scanned picture. Use PAGEUP to zoom in on the screen, see the pad, press PP to place a pad, see the line and follow the PT to route... Just like a child drawing, draw it in this software, click "save" to generate a B2P file.

3. Click "File" and "Open Base Image" to open another layer of scanned color image;

4. Click "File" and "Open" again to open the B2P file saved earlier. We see the newly copied board, stacked on top of this picture-the same PCB board, the holes are in the same position, but the circuit connections are different . So we press "Options"-"Layer Settings", turn off the top-level line and silk screen, leaving only multi-layer vias.

5. The vias on the top layer are in the same position as the vias on the bottom picture. Now we can trace the lines on the bottom layer as we did in childhood. Click "Save" again-the B2P file now has two layers of information on the top and bottom layers.

6. Click "File" and "Export as PCB File", and you can get a PCB file with two layers of data. You can change the board or output the schematic diagram or send it directly to the PCB plate factory for production.

Multilayer board copy method:

In fact, the four-layer board copying is repeated copying two double-sided boards, and the sixth layer is repeated copying three double-sided boards... The reason why the multi-layer board is daunting is because we cannot see the internal wiring. How do we see the inner layers of a precision multilayer board? -Layered.

There are many methods of layering, such as potion corrosion, tool stripping, etc., but it is easy to separate the layers and lose data. Experience tells us that sandpaper polishing is accurate.

When we finish copying the top and bottom layers of the PCB, we usually use sandpaper to polish the surface layer to show the inner layer; sandpaper is the ordinary sandpaper sold in hardware stores, generally spread the PCB, and then press and hold the sandpaper to rub evenly on the PCB. (If the board is small, you can also flatten the sandpaper, and rub the sandpaper while pressing the PCB with one finger). The main point is to pave it flat so that it can be ground evenly.
The silk screen and green oil are generally wiped off, and the copper wire and copper skin should be wiped a few times. Generally speaking, the Bluetooth board can be wiped in a few minutes, and the memory stick will take about ten minutes; of course, if you have more energy, it will take less time; if you have less energy, it will take more time.

Grinding board is currently a popular solution for layering, and it is also economical. We can find a discarded PCB and try it. In fact, grinding the board is not technically difficult, but it is a bit boring.

PCB drawing effect review

In the PCB layout process, after the system layout is completed, the PCB diagram should be reviewed to see whether the system layout is reasonable and whether it can achieve optimal results. It can usually be investigated from the following aspects:

1. Does the system layout ensure that the wiring is reasonable or optimal, whether it can ensure the reliable operation of the wiring, and whether the reliability of the circuit operation can be guaranteed. In the layout, it is necessary to have an overall understanding and planning of the direction of the signal and the power supply and ground wire network.