Apr 7, 2022|Product Innovations and Design

Green is the most common color for PCBs, but a growing number of manufacturers are offering alternatives. However, if you’re thinking about using an alternative to the standard green board, there are a few things you should know about PCB colors and how they can impact visibility.

What Is a Solder Mask?

Are you wondering what a PCB is? A PCB, or Printed Circuit Board, is a device that houses and connects electronic components. They have built-in copper wires inside of the board. Manufacturers also add chips, switches, heat sinks, and other components by soldering them to the surface of the board during the PCB manufacturing process.

What does PCB color mean? The solder mask determines the color of the PCB. The solder mask is a layer of polymer that the manufacturer applies to protect the copper wires and other elements from oxidation. Depending on the composition of the solder mask, the PCB can look green, red, black, or have another tint.

Why Do PCB Manufacturers Use Different Colors?

PCB green is the most common color option, but you can find them in other colors, like red, yellow, white, and more.

There are different reasons for choosing an alternative PCB color:

  • To create a color-coded system for assembling a product that uses more than one PCB.
  • Different PCB colors can indicate different generations within a family of products.
  • Need a certain color for specific properties. For instance, a white solder mask can help prevent overheating due to its reflective properties.
  • Create an aesthetically pleasing product, especially if the PCB is visible.

Types of PCB Solder Mask Colors

Read on to learn more about the most common PCB colors you will come across.

Green

Why are circuit boards green? Designers have adopted green as a standard because this color offers excellent contrast and visibility.

It’s easy to see the trace and blank space with a green solder mask. It’s also possible to spot some defects with the naked eye. Green is a great color for seeing white text and for seeing small elements like pin markings and test point indicators on a PCB.

The silkscreen, which is the template that indicates where to add each component, is usually printed in white. A green PCB makes it easy to see this template.

White

A white PCB can look modern and discreet. However, this color can make it difficult to see the tracing and could result in a higher rate of errors during the assembly process.

The reflective properties of a white PCB can be interesting if overheating is a potential issue, but white is not a common color due to problems with visibility.

Yellow

Yellow is an original color that can make a PCB look very modern. However, it’s another color that will make the silkscreen hard to see and likely result in fatigue and mistakes.

An orange PCB can be a good alternative. The trace and silkscreen will be slightly more visible.

Blue

Why are some PCBs blue? Blue is a color that creates a good contrast with the silkscreen and trace. It also makes it easy to see where the blank spaces are.

Plus, PCB blue can match Arduino boards and create a seamless transition from one component to another if you’re building a prototype that uses one of these boards.

Red

Red is an excellent alternative to the traditional green color. A red solder mask will create sufficient contrast with the silkscreen, trace, and blank spaces.

Red is also a stylish color that looks modern and eye-catching, especially on products with a visible PCB.

Black

PCB black is a color that can look sleek and professional. However, there are some major issues when it comes to visibility.

You should be able to see the white silkscreen easily, but it will be difficult to spot the trace underneath a black solder mask. Another issue is that dark is a color that absorbs heat. It will also make solder and flux stains very visible.

Purple

Purple has some properties in common with blue and red. You can get good contrast with the silkscreen if you opt for a purple PCB. However, because purple is a darker color, it can make the trace hard to see.

Top Reasons Why Most PCBs Are Green in Color

Manufacturers usually opt for a green solder mask because it’s an industry standard. Green is the most common color for a variety of reasons.

Green Minimizes Visual Fatigue

When soldering components manually or conducting visual inspections on a lot of PCBs, it’s important to have good visibility on small components. Green is a color that creates good contrast and reduces visual fatigue.

Green Color Mask Is Physically Superior

A green solder mask makes it easy to spot the trace, the silkscreen, the legend, and the blank spaces. It’s also possible to see problems like slivers or damaged traces with the naked eye.

Bulk Production

Because green is the most common PCB color, manufacturers can offer lower bulk pricing. It’s cheaper for them to produce this solder mask since they can purchase the ingredients in bulk.

How to Select the Right PCB Colors

The right PCB color can depend on your project.

PCB Product Considerations

When choosing a PCB color, it’s important to think about your manufacturing process, the components you will attach to the PCB, and your testing process.

Some colors might not be ideal for small components due to the limited contrast. However, if there is no need to see small elements like pin numbers, colors with low contrast like purple or yellow can work well for PCBs that will use larger components.

The trace thickness is another important consideration. Generally, a thick trace will be a lot easier to see regardless of the PCB color. For thin traces, it’s best to stick to green or red to get the best contrast possible.

Green and red are also best for spotting signs of damage and other issues. If you opt for another PCB color, you will have to incorporate magnification into the testing process.

Glossy Vs. Non-Glossy Surface

There are different types of finish available for solder masks. Choosing between a glossy or matte surface is not a purely aesthetic decision.

A glossy finish can hide solder residues and scratches better than a matte board. Solder ball formation is also easier on a glossy surface.

Price Considerations

You can usually get much lower prices on green PCBs since it’s the most common color. Other colors tend to cost more.

Conclusion

Even though it’s possible to create PCBs with a wide range of colors, designers tend to prefer green and other colors that create a high level of contrast. If you need help with choosing the right color for your project, contact Candor Industries to learn more about the colors we offer and which one would be a good fit for your PCBs.

Author Profile

Sunny Patel
Sunny Patel is the Engineering and Sales Manager at Candor Industries. Sunny is trained as a IPC-A-600 trainer, AS9100 Lead auditor, IPC CID and got his Engineering degree at the University of Toronto.