The Evolution of PCBs and Their Future in IoT

Time to read
3 minutes
Read so far

The Evolution of PCBs and Their Future in IoT

Thu, 05/20/2021 - 08:59
Posted in:

Printed circuit boards (or PCBs) are among some of the most important types of electronic components. Circuit boards act as the foundation for most modern electronics, connecting and supporting all the different components of a device.

Internet of things (IoT) devices require PCBs to work. The unique features and designs of IoT devices, however, can sometimes require new PCBs that can meet the unusual needs of IoT tech.

As demand for consumer electronics grows, driven by new markets like the IoT market, these board innovations may become even more important.

Unique Design Requirements for IoT Devices

IoT devices have a few unique needs that may require unique PCBs as a result.

For example, many IoT devices are small — much smaller than comparable, non-smart devices. 

Wearable IoT devices, like smartwatches and wrist health trackers, tend to be challenging to design for, because they need to be small enough to be practical for daily use. Designers, in response, have to engineer a PCB that can fit into the small form factor of a wearable device while connecting all device components.

Often, these wearable IoT devices are also packing a lot of functionality into a small space. A smart watch, for example, may have a display, a battery, a Bluetooth chip, a handful of sensors and a microcontroller that coordinates these devices. 

The underlying PCB for this device will need to connect and support all of these components — and, in many cases, it may need to be just a few square inches in size.

Designers will have more wiggle room with larger devices, like a smart camera, home assistant or smart thermostat. Even in these larger devices, however, they’ll still face some novel challenges.

Many IoT devices will have a number of wireless modules that allow them to quickly send and receive data to the internet and other IoT devices. PCBs will need to be carefully designed to connect these components.

Challenges of Industrial IoT Device Design

Some industrial IoT devices will also need to be extraordinarily energy-efficient — like low-power pipeline monitors. These sensors are used to monitor for leaks in oil pipelines, which often run through miles of remote and rural areas. 

The sensors aren’t plugged in to the local grid, and may only have a small solar panel as an energy source. Good circuit design can minimize the energy consumption of a device, helping to make these devices more practical.

The users of IoT devices also typically have low tolerance for failure.  Most IoT devices need to be online and transmitting information all the time. While a PCB failure in another device may be an easy fix, a PCB failing in an IoT device can be a real problem for users. 

The more unique a device PCB is, the harder it can be to replace, as well. It’s also going to be trickier to swap out a specialized PCB compared to many other devices.

For these reasons, PCB designers will typically be brought on early in the design process of a new IoT device. This gives them input into the shape of the device and advanced notice on the kind of PCB they may need to design to fit into the space available.

How PCBs Are Evolving to Meet Manufacturer Needs

The design challenges that IoT devices present make certain types of PCBs much more valuable. 

Flex PCBs, for example, are printed on flexible substrate materials, allowing them to bend and twist without disrupting or damage the printed circuitry.

As a result, if you have a device that curves — like a wearable health tracker with a plastic shell that conforms to a user’s wrist — you can use a flex PCB that bends with the device shape. 

High-density interconnect (HDI) PCBs are also a great fit for IoT devices, especially complex ones that need to connect a large number of components. These HDI PCBs use novel manufacturing techniques to shrink essential PCB components called pads and vias. 

By making these pads and via significantly smaller, board designers can achieve high wire density, and allow manufacturers to place components on both sides of the PCB.

These two innovations can also be combined, enabling the use of flex HDI PCBs.

For these devices, effective testing methods can help to ensure PCB quality. For visual inspections, designers often use novel lighting techniques — like diffuse, coaxial and low-angle lighting — to get a better look at the PCB they are inspecting.

Design techniques that allow for more efficient use of space are also extremely helpful. Some 

AI-powered PCB design algorithms can use information on previous circuit board designs to create new circuits that are extremely space-efficient. Many modern electronics design automation (EDA) tools have started to offer AI-based features in the past few years for this reason.

These design algorithms can both work on their own or support PCB designers in making the most efficient boards possible.

Current and Future Challenges for PCBs

Because demand for IoT devices has skyrocketed over the past few years, PCB designers will probably spend more time learning how to design boards specifically for use in IoT technology.  

As IoT devices become even more important, certain PCB innovations will probably become even more essential for the electronics industry.

The growing demand for wearables will likely make unique PCB materials and flex PCBs even more important. The challenges these PCBs can pose for designers may require new design methods and increased use of AI-assisted design technology.

At the same time, growing use of industrial IoT technology may make PCB power draw a key consideration during the board design process.