PCB designer and manufacturing issues.

[info_req]

What type of care should be taken in PCB Design so that nothing could be short circuit during manufacturing and PCB Stuffing in particular for BGA, QFN, and other SMD Packages.


Thanks.

 

[numa]

Best bet is to stay within manufacturer's tolerances ie; track width, clearances etc. And do BBT (Bare Board Testing) if fab offers it.

 

[PCBWING]

DRC rules

 

[khanna_gunjan]

Proper De4sign Rules Setting and DRC After design completion

 

[zula]

firstly you must know the what is the manufacturers tolerance?after you must set the this tolerans in your design rule check.
an example; if the manufacturer say that 'i can 4 mil hole size' now you must the set your hole size 4 mil(min).
regards

 

[marce]

I'd start by becoming familiar with IPC-2222 to 4 and IPC-6011/12

 

[info_req]

Thanks friends. I have got the idea.

 

[grldfischer]

I suggest you to have DFM check for your PCB design. DFM methodology helps designers incorporate manufacturing knowledge during the initial design process, preventing design errors early in the design process and reducing the need for costly corrections later. At present we have free DFM software’s offered by few PCB manufacturers which is of great help to PCB designers. Recently one of my friends mentioned the Sierra Proto Express site, where they have an online tool to check DFM for PCB designers. Has anyone here tried it out?

 

[NIKHILRAJ]

now a days fabricators are capable for making PCB with 5/5 mils (trace width\clerance) and minimum hole dia of 8 mils.
if you can design a PCB with 8/8 mils (trace width/clearance) it will not make any farication issues

 

[grldfischer]

I agree with Nikhil. But it's always better to have a DFM check because if you think your design has minimum trace of 6 mils, and you run through DFM check, it will highlight any areas where the traces are 5 mils. New DFM methodology helps designers incorporate manufacturing knowledge during the initial design process, preventing design errors early in the design process and reducing the need for costly corrections later.

 

[Mousse]

All depend the DFM how difficult the job is. Very fine features increase the risque of shorts. Also, this depend on what kind of process we use to manufacture the ccts.

the board are not cleaned properly before and during DES line, debries left on the board cause shorts after pattern plate. However, we are able to identify those issues in AOI and BBT and scrap the boards.

 

[Kevin Lai]

It's depend in manufacturer's tolerances ie; track width, clearances etc.

 

[marce]

It depends on you designing your board correctly, this means you should learn intimetley how PCb fabrication and assembly is done, and all the various soldering techniques.