Single-Sided Versus Double-Sided PCBs

A group of PCBs

A printed circuit board, or PCB, is an essential component in electronic devices and equipment, such as smartphones, tablets, personal computers, medical devices, LEDs, and industrial equipment. It essentially serves as the backbone for component mounting and interconnections within devices, allowing for advanced functionalities.

Using the wrong type of PCB can lead to many issues, ranging from minor operational inefficiencies, such as overheating and weakened signal integrity, to critical failures. This is why it’s important that you select the right type for your component.

Two of the most commonly used PCB types are single-sided and double-sided. In this article, we’ll highlight the differences between these two and provide guidance on how to choose the best one for your company’s application.

Single-Sided PCBs

Three single-sided PCBs

General Design

As the term implies, a single-sided printed circuit board is designed with a layer of conductive material on one side. This material, typically copper, is used to make the various connections between other components in an end product.

The board itself is thin and flat, and a series of paths called “traces” guide the flow of electricity across it, allowing everything that comes into contact with it to function as intended.

Advantages

Overall, the primary advantage of single-sided PCBs is that they’re incredibly straightforward. There isn’t much to them, which is a benefit that shines through in terms of how easy they are to manufacture.

Because they’re easy to manufacture, they also tend to be a cost-effective solution. Compared to double-sided PCBs, they require less material and can be manufactured faster.

Finally, single-sided PCBs are typically easier to troubleshoot and just as easy to repair. When there are only traces on one side of the board, your engineering team doesn’t have to look quite as hard for the source of any problem you’re experiencing.

Best Use Cases

Because single-sided printed circuit boards are less expensive to manufacture, they tend to be found in consumer electronics and similar devices where designers attempt to keep the price down as much as possible. These devices include thermostats, environmental monitoring devices, and basic diagnostic equipment.

Double-Sided PCBs

Double sided printed circuit boards

General Design

The general design of a double-sided PCB is functionally similar to its single-sided counterpart. As one would expect, the major difference is that there are two layers where connections with other components can be made instead of just one.

Advantages

Because double-sided printed circuit boards are inherently more complex than single-sided ones, they are more expensive. But what you get in exchange for that cost is expanded performance and increased component density.

Double-sided PCBs not only support more complex designs but can also be more compact. Designers have more flexibility in routing, and the double-sided nature also lends to improved signal integrity.

Best Use Cases

As mentioned earlier, double-sided PCBs provide better design flexibility. Based on that, it should come as no surprise that devices with double-sided PCBs are more advanced than devices with single-sided PCBs.

Double-sided PCBs are found in all types of applications, including car dashboards, enterprise phone systems, industrial controls, surveillance and navigation radar systems, flight control systems, UAV communication devices, drones, satellite systems, and more. 

Which PCB Is Right for Your Company?

It’s important to understand that you’re not comparing single-sided and double-sided PCBs to determine “which is better.” You’re simply trying to find the one that is better for your company’s unique set of goals. So, it’s 100% application-driven.

Signal Integrity

If your engineering team is designing something that depends on high signal integrity, you’ll want a double-sided PCB. That doesn’t make a single-sided PCB inherently worse. Single-sided PCBs can be highly effective and cost-efficient in simpler applications where complex routing and additional layers aren’t necessary. Each type of PCB serves a distinct purpose. In situations where complex routing and high signal integrity are required, a single-sided PCB just isn’t the right fit.

Production Cost

The same is true in terms of production cost. If you and your company want to prioritize saving as much money as possible, a single-sided PCB will definitely cost less. However, even if a single-sided PCB is less expensive, it doesn’t necessarily mean it’s the correct choice. The choice between the two still is dependent on your company’s application. As mentioned previously, single-sided PCBs are better for simpler applications where the circuit design is less complex and there isn’t as much of a demand for component density and multi-layer routing.

A thermal image of a PCB

Thermal Management

Any application that depends on proper heat dissipation to function will want to leverage a double-sided PCB. By design, they offer better thermal performance than their one-sided counterparts.

Routing

Real single-sided printed circuit board

Lastly, if your company is designing a complex and intricate device and you need to leave room for the most efficient routing possible, a double-sided PCB can afford that. It simply has more flexibility (not to mention space) for routing traces and components than a single-sided PCB ever could. Single-sided PCBs are best for simple, straightforward, single-layer routing.

Final Thoughts

Again, this is more than determining superiority because neither option is inherently better. 

There will be some situations where a single-sided PCB is objectively better, like in components that don’t require complex routing or require less material and more simplified manufacturing processes.

Likewise, there will be other scenarios where you would never consider using another PCB type except a double-sided PCB. These scenarios include devices with more complex circuits that require a denser arrangement of components, applications with limited space, and applications that require better heat dissipation.

And, for some high-tech applications, like advanced driver-assistance systems and portable ultrasound machines, a stacked or multi-layer PCB might be a better option than the standard single- or double-sided types.

Don’t start with the PCB and hope that it meets your needs. Start with your requirements and work your way back to the PCB.

Get Help From PGF Technology Group

PGF Technology Group is proud to be a leading, ISO-certified contract electronic manufacturer in the United States. Since 1970, we’ve helped clients in many industries, including aerospace, medical device, and military, find the most cost-effective solutions to their challenges. We specialize in electronic assemblies, including PCBs, cables, wire harnesses, and box builds.

Our PCB assembly capabilities include single-sided, double-sided, and Multi Layer. We use surface-mount technology (SMT), mixed technology methods, and offer additional value-added services, including in-circuit testing, automated optical inspection, solder paste inspection, and automated assembly for high-volume production runs.

Please contact one of our experts today if you need help selecting and customizing a PCB for your application, or visit our blog for more PCB resources.