|Ask the Experts|
June 2, 2021
Burned Chip Repair
|Expert Panel Responses|
Surface mount components can be safely removed and a new component can easily be replaced using the same tools. This process is called SMT Rework and involves special tools to locally heat ALL the leads of the component at the same time to the melting point of the solder to both remove and re-solder (reflow) the component. This can be done reliably one or two times (maybe more if the operator is very careful) before the circuit board's solder pads and traces become loose or damaged.
Most all contract electronic assembly manufactures have and use these tools for this purpose: to replace failed or incorrectly placed components or to provide just such a service as you are requesting. It is highly recommended that you use their expertise to do this, whether you only have one board or many boards requiring the replacement.
Although you can purchase the tools they may use anywhere from several hundred to several thousand dollars, depending on the type, unless you plan to become an expert in this skill, and you have lots of boards to practice on, I would not recommend doing it yourself. Make friends with a local contract manufacture to do this.
You may find that if you only have one board to fix,they will do it for little or nothing. Search the internet for contract electronic manufacture in your area and you will likely find one small enough and close by who would be willing to help you out.
Senior Project Engineer
Electronic Controls Design Inc
From the photo my recommendation would be to spend the money on the new board sorry. Something in the system caused this thermal event and it may have damaged more than the component but inner layer to a multilayer board which is not repairable.
President/Senior Technical Consultant
The big decision on this is going to be which of the options (replace or repair) is more cost effective.
Yes, it is expensive to replace the board completely. Repair is certainly an option,but it will take more than a single procedure to repair the damage shown.
Guidance on how to complete the repairs needed can be found in the IPC-7711/21B. There are several procedures which will need to be done since there's more than one thing wrong with the pictured assembly.
You could select one of the listed procedures for each of the following steps:
Component removal: procedures 3.6.1 through 3.6.6 in the 7711
Pad cleaning: procedures 4.1.1 through 4.4.1 in the 7711
Substrate repair: procedure 3.5.1 or 3.5.2 in the 7721
Trace Repair: procedures 4.2.1 through 4.2.5 if there are no internal traces or 4.2.6-4.2.7 if there are internal traces in the 7721
Component placements: procedures 5.5.1 through 5.5.6 in the 7711
The repair can be made and can leave you with a reliable connection.
You need to decide whether or not you have a technician on staff who can complete the processes. If not, then you could send a technician to be certified at anyone of the IPC training centers listed on the following IPC webpage:
If you don't have a technician who you feel is able to complete the training and repair, then you may need to find a repair shop to do the work. Many of the training centers listed on the page above also do contracted repair work or should be able to point you in the right direction.
As I wrote at the beginning, repair is an option. Only you can decide if repair is more cost effective than replacement.
Manager of Assembly Technology
That damage shown can certainly be reliably repaired and the board restored. As other experts above noted, the IPC 7711/7721 should be consulted for the proper repair procedures. Ideally, the work should be entrusted to a highly skilled, properly trained operator.
Circuit Technology Center
The process would include the removal of the chip then subsequently the removal of the burnt laminate material. The procedures for these efforts are all defined in IPC 7711/7721 procedures 3.5.1/3.5.2/3.5.3.
This work has been done reliably in the past. Due to the existing value added on this product the skills of the operator must be high with lots of experience.
As for guidance make sure your operators have attended and been certified to IPC-7711/7721.
We don't normally make recommendation in this forum, so if this information is needed please don't hesitate to contact me at your convenience.
Vice President, Technical Director
In general, whether you can effectively make the repair depends on:
Finally, keep in mind that if an IC has burned up, it has drawn excessive current, and there may be collateral damage;alternatively, something else may have caused the excess current, and the burned IC may be the collateral damage. The risk is that you repair the board,and it fails again, maybe immediately, maybe later. If it is going back to a customer, what will a repeat failure mean?
This can be repaired. The questions I what and how much is damaged as well as what caused this and id it going to happen in the future with other assemblies?
What I see is that the component has to be replaced for sure and then the traces have to be checked for internal board damage. Should be any open connections,they can be fixed by external jumpers.
Schematics and Gerbers will be necessary too to understand the board layout.You can contact me to discuss more.
Engineering and Operations Management
I am not trying to promote someone but I work for Contract EMS provider and we ship our boards for repair to Circuit Technology Center and they are good at board repair. You may have to provide a picture of the defect along with the PCB files in case if any board repair need to be performed for quote.Sundaram, EIT LLC
There is not quite enough information, but based on the picture alone it appears as if a large blob of solder damaged the component after assembly and reflow. I cannot see any significant PWB damage, but it is hard to tell. Did the board pass any type of flying probe or functional test? Did the damage occur as a result of an electrical short when powered up, or was it in fact just a blob of solder? If this happened during power-up at test then Dr. Munson is correct, you may as well scrap the assembly because all of the other components in that particular circuit may have been subject to an electrical overvoltage condition (EOS). But if the damage is just from a blob of solder, then there is probably no need to scrap or replace the entire assembly, and simply removing the damaged component, cleaning the area, and replacing with a new component (and re-testing) should fix it.
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