Advanced Rework at PHYTEC

At PHYTEC we pride ourselves on the many services we offer that go beyond the System on Module. One of our most utilized services is advanced rework. I recently spent a day at our Bainbridge Island office for hands on experience to learn how our in-house tools help PHYTEC customers every day.

PHYTEC’s High Performance Ersa Rework station

So, what exactly is advanced rework? In a nutshell, it is populating or depopulating components on a PCB. Seems pretty straightforward, but there are advanced tools and knowledge required to do it right, and many times this just isn’t a possibility outside of a manufacturing facility. To do rework locally in our U.S. office we have a standard hot air and soldering iron setup like a typical electronics lab for 0402 and leaded packages. In addition, our advanced rework station allows for bottom heat, precision placement, and thermal profiles to do high quality and advanced rework procedures like removing and soldering BGA components. However, having the advanced machine and tools would mean nothing if we didn’t have the brains behind it.

Spencer Black, the rework master

Enter Spencer Black, PHYTEC’s very own advanced rework master. He has been building his skills up to a rework certification since his time at Western Washington University where a major project introduced him to the world of rework. He then joined the PHYTEC team in Summer of 2017. Shortly thereafter Spencer spent a week in Vancouver getting official solder training, and received his IPC-7711/21 certification. It was here he learned no amount of studying can get you to a high level of expertise like lots of repetition and hands-on practice.

Starting advanced rework

After my preliminary rework research, I decided it was time to hang out with Spencer and see him in action. I was able to choose which component I wanted to depopulate from a dead board, and went with the processor. I peeled off the serial number stickers, and we fired up the machine. From there we clamped the board into the machine tray, and applied some flux around the edges of the processor to encourage the solder to flow underneath the BGA when reaching its melting point of 217°C.

Removing the BGA: Placing the temperature probe

Next we chose the appropriate thermalprofile and maneuvered the temp probe so it was as close as possible to the processor. The onboard temperature reading works directly with the profile and machine to apply more or less heat on the top and bottom of the PCBA.

 

Spencer’s famous cookies

Surprisingly, what’s taken Spencer the most time to nail down has been the thermal profiles, which can only be perfected to a science after lots of trial and error. Spencer loves to bake, and says rework is a lot like baking; you have to get the recipe just right every time in order to get the results you’re aiming for.

phyCORE-OMAP4 SOM and Processor after rework

Once the profile has been selected and started, depopulation begins. You want to make sure you’re paying attention to the board and profile until the machine is finished, to ensure nothing goes awry. After 5-10 minutes, a small 10mm vacuum dropped down to pick up the component, and voila! We then let the board cool down. The last thing you want to do is grab a hot PCB off the tray, as the machine temperature rises between 230 and 240 degrees Celsius for this type of job. Here are my results, the phyCORE-OMAP4 SOM with the processor removed

So, you depopulated a component. Congrats! What’s next?

Typically we would clean the pads on the PCB and solder down a new component – in this case we might want to solder down a new processor variant. As for the processor we removed, we can also re-use this component. Spencer has become so skilled at his craft that he can even re-ball a processor right here in the office!

 

Spencer stays consistently busy with a new rework project almost weekly. This usually consists of standard processor and memory changes, but also has become quite valuable for development, as it allows us to experiment and try different things very quickly. It allows us to change configurations on already-built product to give our customers exactly what they want in a timely manner so they can start development. Without this advantage it can take up to 4 weeks to source components, manufacture, and test new prototypes. PHYTEC’s advanced rework capabilities save time and hassle, and we can usually turn around reworked hardware the same day.

Ready to get started?

Let’s go. Get in touch with PHYTEC today.