How Component Packages Can Affect the PCB Production Process
There are a lot of different factors to consider when you’re working on a new PCB design, so the actual component packages being used will often get only a cursory thought. For that microcontroller, you might choose to buy whatever package already has a footprint in your CAD software; for that one pesky decoupling cap, you might shrink it down to a smaller package just to get it out of your way.
At Bittele, we’re here to help make sure that every part of the PCB Fabrication and PCB Assembly processes go as smoothly as possible for you, so we want to remind you that those often-overlooked component packages can have a big effect down the line. Before you finalize your design, you might want to think about these component consequences, and take another look at your Bill of Materials.
Complex parts are sometimes required for a complex product, but it is important to understand Our Capabilities for Complex Parts, and the additional considerations that must be made for these components in order to better plan and budget for a product during the design phase.
For parts without external leads, such as BGA, LGA, QFN, CSP, & FLIP-CHIP, or POP technology, Bittele must use X-Ray inspection during the final quality check of the assembled PCBs. This verification process incurs some extra PCB Assembly cost compared to QFP-style packages. Rework is also much more difficult for these types of parts, which makes the entire assembly process much less forgiving. The very fine-pitch versions of these packages will sometimes require complex processes as well, such as Via-in-Pad Filling.
At Bittele, we handle production loss considerations on our end of the equation, so you never have to worry about ordering extra parts or extra boards to make sure you get what you need. There is always a risk of production loss, and that risk is greater for some component types than it is for others, so in order to make sure we can fill your order on time, every time, we make sure we have extras on hand for particularly risk-prone package types.
The biggest production loss culprits are small passive packages, like 0201 and 0402 resistors and capacitors. Bittele can handle assembly for these types of parts, but we have to build the expected production loss pricing into your project quote. To minimize the cost of your project and protect against production loss, we recommend sticking to 0603 or larger packages whenever possible.
Heavy or Unwieldy Packages
The concern with particularly large or heavy parts is mainly in shipping and handling costs. Parts such as transformers or power resistors will incur much higher shipping costs for their initial transportation to Bittele’s assembly facilities, as well as the final shipment of the assembled PCBs to the client. It is not always possible to eliminate such parts from a design, but it is important to be aware of these potential sources of extra cost well in advance.
Parts requiring manual assembly will decrease the efficiency of a mainly-automated PCB assembly process. Through-hole parts on a majority surface-mount design or mounting hardware for final assembly will require additional attention from Bittele’s staff, which drives up both the cost and the lead time of a project.
Multiple Unique Packages
Simply put: the greater the number of unique component packages in a given BOM, the greater the time requirement for Bittele’s DFM/DFA Check prior to PCB assembly. The DFA check includes a comparison of each land pattern in the PCB layout against the datasheet footprint for each part in the BOM. This comparison necessarily becomes more onerous as the number of unique packages is increased. If the DFA check process does discover footprint-to-land pattern mismatches, the necessary design revisions will also be more quickly completed when fewer unique land patterns exist across the design.
During the PCB Assembly Process itself, different types of component packages often come with their own unique demands and process controls. As such, a reduction in the number of unique package types will simplify the PCB assembly process as a whole, thereby reducing both lead time and potential for error.
We hope that this article has helped to remind you that your component packages deserve a second thought! If you find yourself with any further questions about the package types in your design, or to get an official quote for PCB services, please feel free to Contact Us any time. We can be reached via email at firstname.lastname@example.org, or toll free at 1-888-812-1949.