9 PCB Silkscreen Design Methods You Must Know

Silkscreen on a printed circuit board isn’t just for looks. It tells you where components go, which way they face, and even helps during testing and repair. A clear and well-planned silkscreen can save hours of assembly trouble and reduce costly mistakes. Let’s break down what PCB silkscreen is, what information it carries, and the 9 PCB silkscreen design methods that make boards easier to assemble and maintain.

What Is PCB Silkscreen?

PCB silkscreen is the printed text and symbols you see on the surface of a circuit board. It usually includes part numbers, polarity marks, pin indicators, logos, and compliance labels like UL or CE. While it’s added during FPCB fabrication, silkscreen becomes most valuable during assembly and testing.

What Information Does Silkscreen Show?

A typical PCB silkscreen can include:

• Polarity and orientation marks

  

• Test point identifiers

• Component reference designators (Ref Des)

  

• Component outlines and boundaries

• Pin one indicators

• Company name or logo

  

• Version number, batch code, or date code

• Warning or regulatory marks (CE, FCC, UL, RoHS)

This information ensures parts are installed the right way and that the finished board complies with industry standards.

Common Silkscreen Colors

White: The most widely used—easy to read and manufacture.

Yellow, Red, Black: Sometimes used for contrast in design stages.

Pink: Rare and not recommended due to poor manufacturing compatibility.

How Is Silkscreen Applied?

There are three main production methods:

Screen Printing – The traditional method using epoxy ink. Low cost but less precise.

Liquid Photo Imaging (LPI) – More accurate, similar to applying solder mask.

Direct Legend Printing (DLP) – The most precise, using UV-curable acrylic ink. Best for fine text and dense layouts.

9 PCB Silkscreen Design Methods

1. Choose the Right Font Size

Keep text large enough to read. Typical sizes are 25–35 mil in height with 5 mil line width.

2. Label Component Pins

Always mark pin numbers on connectors and ICs. This avoids mis-wiring and simplifies debugging.

3. Keep Reading Direction Consistent

Use no more than two orientations (left-to-right or bottom-to-top). This makes the board faster to inspect.

4. Limit Component Orientation

Try not to place silkscreen text in four different directions. Stick to two for easier assembly and repair.

5. Show Component Polarity

Clearly mark diodes, electrolytic capacitors, and connectors. A missing polarity mark is one of the top causes of assembly errors.

6. Place Reference Designators Close

Keep part labels near the component they belong to. If the layout is tight, use arrows or boxes to point to the right spot.

7. Avoid Printing on Pads

Never place silkscreen over solder pads. It reduces solderability and can make markings unreadable after assembly.

8. Stay Clear of High-Speed Traces

Avoid putting silkscreen on high-speed signal lines. It can affect impedance and signal quality.

9. Pay Attention to BGA and QFN Packages

For complex parts like BGAs, align silkscreen outlines precisely with the chip body. This helps during placement and rework.

Good silkscreen design improves assembly accuracy, testing efficiency, and long-term serviceability. By following these 9 PCB silkscreen design methods, you’ll make your boards easier to work with and reduce the risk of costly errors.

Looking for a PCB partner who pays attention to these details? At Flex Plus, we provide high-precision PCB manufacturing and assembly with professional silkscreen printing. Reach out to us today and let’s discuss your project: www.flexplusfpc.com.