How to Flip PCB design in PADs, ORCAD and EAGLE

Hi all,

I wanted to flip PCB design where only components are place on top side while routing is to be done from back-side by looking at already made PCB for reverse engineering in PADs, ORCAD and EAGLE software.

I used to do the same with PADsPCB DOS versions long time ago but on its Window version, it missed many nets, tracks and vias. I don't whether it can be done on older ORCAD layout (>v9) or EAGLE.

Following are the steps I tried to do:
1) First make available all the Decal of all the parts needed on PCB that are required for Reverse Engineering.
2) Place all the components and add all visible Vias from component Top) side.
3) FLIP the board layout using menu command.
4) Manually routes all the pins, pads and Vias by looking at the back of PCB (now in front after flipping) and using earlier PCB that needs to be reverse engineering as a guideline.
5) FLIP the completed board layout once again using menu command.
6) Extract Net-list for use with OrCAD
7) Rearrange the circuit blocks on OrCAD, manually.
8) Go back to PADs PCB and optimized PCB layout using circuit flow.

I was able to do the same successfully with latest version of Altium but failed on Windows version of PADS. I want to use PADs PCB or OrCAD or EAGLE because of its highly flexible, easy keyboard's shot-cuts and editing options for fast manual routing practices which I used to do for many years.

Can anyone suggest Tools or Add-ins or Tips/Techniques to do same thing?

Thanks in advance with regards,
--micropar--

I saw your earlier post and I couldn't understand what your were trying to do then so I don't think posting on another forum will help!

Your objective isn't clear to me, nor is your method.

Keith.

Hi keith1200rs,

Thanks for inquiry, asking for more clarifications.

My main objectives are to reverse engineer my own PCBs I made years ago whose original PCB design data files I lost somehow. Now I only have actual PCBs made during those days which I want to improve and test the same circuits using latest and newer chips available.

To do these, I first need to prepare original circuit diagram that I had lost too. Most easiest way is to manually trace each PCB's tracks by looking at back side of PCB. But this is very time consuming for the lots of PCBs, made during those days. Instead I have mentioned steps of what we used to do while I was working as a professional PCB designer, catering to many customers who used to brought to us their competitors PCB for copying or reverse engineering.

Now is it clear? Or need More explanation? Don't worry, I will be happy to clarify as these old techniques of coping PCB still valid even today for many applications, helpful to many newcomers.

In fact, now there are many ready made software available on net, which can directly create professional PCB layout right out of scanned JPEG file of unsoldered PCB. But they are not useful to me as my most PCBs are populated with components and still working, which I don't want to spoil by de-soldering.

Thanks in advance with regards,
--micropar--

Do you have the original Gerbers and drill files? I know some packages can import them (but not Eagle which I currently use).

So, if I understand you correctly, you want to make an 'image' of one side, then of the other and combine the two - hence the need to mirror one side? It sounds easy enough to do. I guess you should only put the holes/pads on one of the images. I assume they are through hole on 0.1" pitch which should help.

What PCB package were they done on and do you have the original files? I guess not because you could possibly import those,

I think it should be easy to do in Eagle but I will do a test to check. It might take a few days as I have a deadline to deliver some equipment this week and have to go away for a couple of days.

Keith

Hi keith1200rs,

Thanks for your response.
You wrote:

So, if I understand you correctly, you want to make an 'image' of one side, then of the other and combine the two - hence the need to mirror one side?

Click to expand...

Yes Exactly. Glad that now you understand my idea. You can even expand my idea to copy multi-layer PCB also.
How? Very simple.
Either (1) copy top and bottom layer, and make PCB using my idea, then make BBT (Bare Board Tester) jig to find out connections on inner layers or (2) Use floating probe type BBT where you can directly use original, unsoldered PCB itself to create circuit diagram for reverse engineering.

Sorry I lost Gerber and Image files too. So the only option left is to manually copy and route PCB on PADs or OrCAD or EAGLE using the techniques I discussed above for reverse engineering.

Awaiting for your Eagle feedback....

Thanks in advance with regards,
--micropar--

I have had a look with Eagle and it seems no problem. You could put the components on "both sides" to begin with and then it is easier to align the two sides when you flip, although I guess you can do that from the outline. In Eagle the command is "mirror". The demo version should enable you to try it if you don't have the full version. In Eagle it only grabs the parts which are visible to move so it is easy enough to move tracks on one side without affecting the other. Also, if you hide the "origin" of a component it is still visible but cannot be moved, which can be handy. I have assumed through hole components.

Keith.

Hi keith1200rs,

Many thanks for comments. I will try on Eagle as your suggestion and post feedback here. But I am not well convergent with Eagle compared to PADs (POWER PCB) which was #1 software in those olden days. I don't know how efficient are their manual routing commands together with Mouse + Keyboard shortcuts. For one thing where PADs is strong in this kind of manual routing for reverse engineering: In PADs, you just move mouse exactly along the path of track drawn on ready-made, copying PCB without any care for DRC, and PADs routes instantly and create track exactly following mouse movement. I don't know whether that kind of feature available in Eagle.

What about Flip or Mirror commands in PADs (Windows version: POWER PCB) and ORCAD? Is anybody there to help?

Thanks in advance with regards,
--micropar--

In Eagle, if you just make a PCB (i.e. with no schematic or rats nest) you can just put tracks where you like, clicking to create a vertex. If it lands exactly on a pad or another track it will make a net connection so then you can drag the part and the track will also move as it will be connected. I think you can then also extract a netlist out of it. It is a lot more tricky with surface mount devices on weird pitches (but fine if you are doing a PCB the "right way round" with a schematic and ratsnest because it will finish off the connections for you even if they are off grid or if you click short of the end).

Keith.