PCB clone general steps
Step 1: Preparation
Get a good circuit board and scan it as a backup before removing the components. Remove the higher component first, and then perform a second scan to record the image. Do the cleaning work before scanning to ensure that the IC model and the characters on the PCB are clearly visible on the picture after scanning.
Step 2: Disassemble components and make BOM
Use a hot air gun to heat the component to be removed. The removal order is first the resistor, then the capacitor, and finally the IC. Before disassembling, a form with recorded items such as tag, package, model, and value should be prepared. After removing all the components, use a bridge to measure its value. After the measurement is completed, enter the data into the computer for archiving.
Step 3: Remove the dirt on the surface
Remove the remaining tin dross on the PCB surface of the removed component, and pay attention to the temperature of the electric iron should not be too high, so as not to burn the ink.
Step 4: PCB clone
After scanning the surface image, it is determined as the top layer and the bottom layer, respectively. First, package the components (including small screen printing, pad diameter, and positioning holes, etc.). After all components are completed, place them in corresponding positions and adjust them to match the original board.
Sand the surface with sandpaper to expose bright copper.
If it is a multi-layer board, take 8-layer board as an example:
After one or eight layers have been copied, then one and eight layers of copper are ground off, then two and seven layers are copied, then three and six layers, and finally four or five layers are sufficient. During the operation, make sure that the size of the basemap is correct, and then adjust the position of the PCB components one by one so that they completely coincide with the basemap.
Step 5: Check
Using image processing software, combined with PCB drawing software and circuit physical connection relationship can make 100% accurate judgment.
In the traditional method of clone PCB in the interview, if the non-destructive method is adopted, the circuit board is scanned by CT to obtain a projected image, and then a three-dimensional image is obtained using image reconstruction technology, and then the images of each layer can be obtained by correcting and layering.