PCB Fabrication and Assembly Considerations to Reduce Costs
Companies are always looking for ways to decrease costs. For electronics companies, PCB manufacturing is one place this can be accomplished. However, there is always a compromise between cost and quality. There are times when quality can be sacrificed and times when it would not be appropriate. Here are five ways we have found to be successful ways to reduce cost.
Plan the size of the board upfront
The size of a PCB can dramatically and directly affect the cost of fabrication. Routing may be tight, leading engineers to increase the board size. However, this may cause issues when it comes time to panelize the boards. To decrease costs, it is important to utilize as much of the panel material as possible. Something as simple as adjusting the board size a small amount can allow more boards to fit on one panel. Most manufacturers use panels that are 9x12", 9x24", 18x12", and 18x24". Using dimensions that divide evenly into these sizes will increase yield and decrease costs.
Consider using higher quality materials
We have often seen customers request cheaper, substitute materials in order to decrease costs. This may be appropriate for small prototype runs where the boards will be tested immediately. However, these cheaper materials often begin to cause failures in the functionality of the boards quickly. They may test just fine in the lab, but they will begin to fail once in the field under different environmental conditions. Temperature, vibration, and moisture can affect the board’s functionality, mainly when using cheaper materials. It is advisable to consider these issues when choosing materials.
Use standard printed circuit board shapes
Standard PCB shares are squares and rectangles. These are considered standard because they make panelizing the boards much more straightforward and result in less waste. However, there are often times when an enclosure or other aspect would create the need for a custom shape. More unique shapes require more time and tooling through the CNC routing process. Also, cutouts both on the edges and internal cutouts add cost. Again, it sometimes is beneficial to use standard PCB shapes for prototype testing, especially if it is suspected that the board has a higher than average chance of failing in some manner, then redesigning it with the custom shape.
Utilize industry-standard components
Over time, the PCB electronics industry has developed standard sizes for many components. This is because of the way the automated component assembly process works. The original intention in the development of surface mount components was based on component handling. Parts needed to be designed so that pick and place machines could easily manipulate them. These parts make these processes more efficient, saving costs. Non-standard components generally require a human being to install them rather than a machine. The more human contact, the higher the price. If possible, it is best to stick to standard components.
Consider longer lead times
Lead time for PCB manufacturing is a massive factor in determining cost. This is particularly true when a PCB is more complex, such as having a high layer court, blind and/or buried vias, or impedance and dielectrics. When manufacturers get quick turn orders, they have to interrupt the current manufacturing processes. For example, they may have ten separate orders set up already and then have to add one in the middle. This takes time and adds cost. If possible, it is always best when planning a project to allow at least twenty business days to turn the boards.