Obtain the schematic circuit by pcb

Hi,

I scanned a printed circuit board, and I got the file PCB made OMNIGLYPH (CIRCAD ...),

with all the components already in place.

There is a program to obtain from file PCB, the schematic circuit ?

NB: I can convert PCB file Circad TANGO II or in other formats ...

It would be a great help to find a solution, thanks.

Hi,

From what i understand, Superman can do it because he can use his X Ray vision to see through the board to view the four later board traces (har har).

For simpler boards, i have scanned and traced the copper by hand on the computer screen, and correlated the holes to the components on the top of the board. Dual side boards are hard to do though because many of the traces run underneath components and therefore can not be seen correctly. I had trouble once with a board that was small, where one component hid the traces so i could not be sure where they ran to. I had to use an Ohm meter and a little guesswork.
Boards with more then two layers (like with 2 sides and one inner layer) will be impossible to view so you're stuck using an Ohm meter and hope you can get decent measurements in order to tell what is really connected. It's quite time consuming however. I only do this when i really have to.

sorry you cannot obtain schematic from any PCB file....you got to go through it by hand and DMM

The PCB file is a physical netlist of traces, pads and holes, and component physical properties with no info on the device logic symbols or part numbers.

The Schematic is a logical netlist of everything that is missing on the PCB file.

Hi,

Oh ok so he wanted to get the schematic from the PCB file itself, not the physical board. I think there is an online psychic service that does that but they are pretty expensive (he he).

Yeah, the schematic is a totally different drawing than the PCB layout. The PCB layout often shows the outline of the part, but no part numbers that would be needed to get the whole schematic.

Alas, its something that must be done manually. Tracing out schems from boards is something I have done for a while now - it is tedious, some guesswork can speed it up, but ultimately, a pencil, bit of paper, and a mug of coffee are the tools I used. Normally you can (try) to eliminate subcircuits like power supplies etc.. leaving only the part you're interested in.

With a real board, as suggesting a continuity tester, ohm meter is used. One can also photograph both sides of the board, mirror the bottom, make the top semi-transparent, and overlay them. As for a PCB file, try and get an image for it with different colours for different layers, then eyeball it )

Hola Tony

In this thread what you have in mind is mentioned, considered and explained. To avoid reading such a long thread, start from the bottom post.

Otherwise, maybe too wordy but very informative and interesting. Enjoy.