A printed circuit board (PCB) can quickly rise to become one of the most expensive parts of the entire product when designing and producing it, so reducing the cost of the PCB is one of the primary aspects that may prove advantageous for reducing the overall production cost. Reducing PCB size, using appropriate components, and utilizing suitable design methodologies can significantly cut down on PCB costs. In light of this, this post will go through some of the most prevalent methods for cutting down on PCB costs during the design and fabrication phases. Many different PCB design methods, such as: have been covered in our prior articles.
- Efficient Placing of Thermal Vias Improve Heat Management
- Via Stitching in PCB Design
- Understanding Blind, Buried, and Through-hole vias in PCB
- How can Teardrops help in Improving Quality and Stability of your PCB Design
If you want to find out more about PCB design and production, you can look into those. So, let’s check out some ways to cut down on PCB production expenses.
Reducing the Size of the PCB
One of the most typical ways to reduce PCB costs is to reduce the size of the PCB. The size reduction of the product is another good result of shrinking PCBs, which can be useful in a wide variety of contexts. In the past, the size of the PCB was mostly determined by the components that could be used. These were typically through-hole components.
It is now possible to immediately reduce the size of a PCB by switching to a surface-mount version of any component, including an integrated circuit. To grasp how drastically the board is reduced by component sizes, please refer to the images below.
You can notice the size difference between a through-hole package and an SMD 0805 package in the photographs up top. It is now abundantly evident that resistors of the same value and wattage can be utilized in significantly less volume. You can even use two separate resistors, one on top and one below. In addition to the larger 0805, much smaller sizes such as 0603, 0402, 0201, etc. are also available. This is also reflected in semiconductor components like diodes and inductors. Even if you just use half as many capacitors and half as many resistors in your circuit, you can cut the board size in half.
Other ways to reduce component size on PCB:
See the resistors below to see how the SMD resistors can be decreased even further with careful design and component selection.
Comparing 8-pin SIP and 0805-package resistors. Cutting down on PCB size is the equivalent of making the appropriate moves in a chess game. The costs of the SMD components, both individually and in terms of assembly, are lower than those of the through-hole alternatives. Again, this is for good reason, as through-hole components necessitate more work to install in the form of severing component leads and soldering them into the board.
Reducing unnecessary Layers as well as bad Layer Specifications
For various reasons (Thermal compensations, unpleasant routing experiences, etc.), individuals frequently add extra layers to their networks that aren’t necessary. Reducing the number of layers used in the circuit board’s manufacture from 6 to 4, then 4 to 2, and so on, can result in significant cost savings. It’s crucial to think about strategies to lessen the number of layers on the board whenever you can. However, a greater layer count may be required for improved signal quality and the overall performance of a circuit board if the board has ball packages or lengthy routings. It is crucial to make the correct selection regarding how many layers one should use when making a circuit board design, as the greater cost is beneficial in such circumstances to save additional rework money.
High PCB fabrication costs are sometimes the result of designers giving incorrect layer parameters to the vendor. Is a 70um copper thickness across all layers required for your design? Is it feasible to produce the board with Top and Bottom layers of 17.50um and interior layers of 35um, or vice versa? Many manufacturing expenses will be cut as a result. In addition, please provide the appropriate PCB creepage distance.
Reducing PCB Cost by changing PCB Materials
When deciding on a material, price becomes an important consideration. Although generic FR4 PCBs will suffice in most situations, there are a few exceptions. By “PCBs for LED,” I mean the circuit boards used to power an LED light bulb.
If you choose your board materials carefully, you can cut costs. A more expensive choice is often unnecessary and can be considered a luxury when the ordinary FR-4 Board is all that is needed to complete the job in a wide variety of contexts. Unless there is a specific need, a temperature range of 130-140 degrees can be used for all situations.
When the PCB thickness isn’t standard, prices rise. The typical PCB thickness is 1.6mm. Changing the PCB’s thickness during manufacturing will increase or decrease costs.
Solder Mask and Legend Color:
You should use a green solder mask and avoid creating PCBs in bright colors like black, red, blue, etc. Having so many color possibilities adds a significant cost to fabricating a PCB. Since it is the least expensive alternative, the Green Solder mask is frequently utilized in PCB production. The Legend Color must follow the same convention. White is by far the most typical legend color. If you want your PCBs to be a different color, like black, you’ll have to pay a lot more. While this is generally true, there are certain manufacturers who treat all solder mask and silkscreen variations as the same pricing.
Immersion Gold/ENIG is an expensive PCB option that should be avoided unless absolutely necessary. High-speed, impedance-controlled traces necessitate this in order to maintain proper signal integrity locking. Do any basic boards suffice for this task? The usage of immersion tin or HAL(Sn-Pb) can help to lower manufacturing costs.
Routing related compensation
During PCB production, adding Buried and Blind Vias increases costs significantly. Altering the architecture such that it can be routed without needing Buried or Blind Vias. Additionally, occasionally people install components in a sequence that makes the routing easier, but then they have to solder the component manually during the assembly process. It’s not a cheap choice.
Believe me, in almost all cases, a good design practice could reduce the chance of using buried or blind Vias until it is a truly dense board that requires signal integrity where buried or blind Vias are required.
Adjust order volume and lead time
Finally, order volume is a crucial factor in reducing production cost, be it for components, assembly, or manufacturing PCBs. Its value decreases as the cost increases. The price per PCB produced decreases with increasing order quantity. You can plan and alter the order volume to match the capacity of the PCB manufacturer you’ve chosen. In the future, it will be necessary to compare the cost of the necessary PCs with the expected demand. However, before going into production, ensure sure the board has undergone thorough testing during the POC (Proof of Concept) phase. It’s a waste of time and money to place an order without first evaluating the PCB.
You should find out the lead time right now. Before beginning a manufacturing project, it is best to order the PCBs when you have time to spare and a well-defined, time-based goal in mind. The laws governing lead times vary depending on the supplier. If you need to order a PCB with a rapid turnaround time, expect to pay a premium. Therefore, the lead time should be modified so that the cheapest possible PCB quotation is obtained. Though it might not seem like much to save a few dollars on a single board, the savings could add up to significant sums when applied to larger production runs.