Keyboard PCB – A Complete Guide

Keyboards are everywhere - whether it's the daily used laptop, high-performance gaming rig, or the common office setup. They all rely on one core component: the keyboard PCB. Under each set of keycaps lies this seemingly ordinary but crucial keyboard circuit board. It is responsible for connecting and controlling switches, LEDs and controllers, ensuring that every keystroke can be accurately recognized and responded to by the computer. Without it, the entire keyboard cannot function properly, let alone provide a stable and efficient input experience.

This article will introduce keyboard PCBs from multiple perspectives, including the basic concepts, common types, layout methods, key components of keyboard PCBs, as well as the differences between mechanical keyboards and membrane keyboards. In addition, it will also introduce the key factors that need to be considered when purchasing a custom keyboard PCB or a hotswap PCB, and help you understand how to select the appropriate keyboard assembly manufacturer or partner.

What is a Keyboard PCB?

Fundamentally speaking, the keyboard PCB is the most core foundation of the keyboard. It is like the "brain" and "nervous system" of the keyboard, responsible for transmitting every keystroke.

The function of the keyboard PCB is very simple. It connects mechanical switches, LEDs, Diodes and stabilizers. allowing each key press be transmitted through the keyboard circuit to the microcontroller, and the microcontroller then translates these actions into digital signals that the computer can recognize.

So, when you press a key on a mechanical keyboard, the keyboard schematic transmits the signal to the processor through the keyboard circuit board. The computer will then display the corresponding letters, numbers or commands. The keyboard simply cannot be used without a properly functioning PCB for keyboard.

In addition, custom PCB keyboard can offer more freedom to players and enthusiasts. You can design, program and even modify the details of the keyboard hardware by yourself. Whether it's the portable small-sized 60% PCB or the 75% keyboard PCB that combines functionality and compactness, they can all meet different needs and personalized choices.

Types of Keyboard PCBs

Not all keyboard PCBs are the same. They differ in structure, supported layout and functionality. From the flexible PCB suitable for portable devices to the hotswap PCB prepared for DIY enthusiasts, each keyboard circuit board has its unique advantages. Understanding these classifications can help us select the most suitable keyboard PCB to meet personal typing habits and project requirements.

By Construction

We can classify keyboard PCBs according to their structure, and each design has its own advantages and disadvantages.

• Flexible PCB - Made from thin plastic material, it can be bent and folded. It is highly suitable for compact and portable keyboard designs. However, this type of keyboard is not very durable and may get damaged after long-term use.

• Rigid PCB - The most common keyboard circuit board, usually made of FR4 fiberglass. It is strong and stable, suitable for long-term and heavy use, and therefore widely applied in most mechanical keyboard PCBs.

• Semi-Flexible PCB – A combination of flexible and rigid structures. It provides higher strength while maintaining a certain degree of adaptability, and is very suitable for custom keyboard PCBs that require special shapes but cannot sacrifice stability.

By Keyboard Layout

Different keyboard PCB designs determine the layout of the keyboard and directly affect our typing experience and desktop space utilization:

• Full-size (100% / 96%) - Featuring a complete function row, numpad and arrow keys, it is the top choice for office workers and professionals.

• Tenkeyless (80% / 75%) - Removing the numpad but keeping most of the functions. The 75% keyboard PCB not only saves space but also offers comprehensive functions, making it one of the most popular layouts at present.

• Compact (65% / 60%) - 65% and 60% keyboard PCBs are the most favored layouts by enthusiasts. They retain the core keys while significantly reducing the size, making them highly suitable for DIY keyboard PCB projects and portable use.

• Mini/Specialty Layouts - Smaller layouts, possibly with only 40% or fewer keys, mainly targeted at enthusiasts, or for custom PCB keyboards to meet unique keyboard hardware requirements.

By Functionality

Keyboard PCBs not only differ in construction and layout, but can also be classified into various types based on their functions:

• Hot-Swappable PCB (Hotswap PCB) - Supporting hot-swapping. Users can directly plug and pull mechanical switches without soldering. It is the first choice for DIY keyboard PCB enthusiasts because the switch replacement is simple and quick, making it convenient to try different typing feels.

• Wireless Keyboard PCB - Offering Bluetooth or radio frequency (RF) connectivity, freeing the keyboard from data cables and making it more suitable for modern portable or minimalist desktops.

• RGB Backlight PCB - Very common in custom PCB keyboards, it supports individual lighting for each key, providing rich lighting effects, and is very popular among gaming and personalized users.

• Standard vs. Mechanical vs. Membrane Keyboard PCBs - Mechanical keyboard PCB uses independent switches, durable and customizable. The PCB of the membrane keyboard uses rubber domes, which is low in cost but has a short lifespan. The standard keyboard PCB covers common office and notebook scenarios.

Components of a Keyboard PCB

The keyboard PCB schematic is not merely a few simple copper traces. In fact, it integrates a variety of key components to jointly ensure the normal operation and stable experience of the keyboard. The main components include:

• Processor (Microcontroller Unit) - This is the brain of the keyboard PCB. It can receive signals from the keys and convert these signals into digital commands that the computer can recognize.

• Scan Circuit - Composed of a series of circuits and electronic components, it is responsible for detecting key presses between rows and columns. When you press a certain key, the scanning circuit can immediately recognize the change at that position and transmit the signal to the processor.

• Matrix - This is the backbone of the keyboard circuit. The keys are arranged in rows and columns. The matrix can handle the situation where multiple keys are pressed simultaneously, avoiding misjudgment and ensuring that complex inputs can be accurately recognized.

• Diodes - A diode is usually added under each key. Its function is to prevent "ghosting", ensuring that even if you press multiple keys simultaneously, the signals do not interfere with each other, thereby enhancing the accuracy and reliability of input.

• LEDs & RGB Drivers - These components control the backlight effect of the keyboard and are particularly common in mechanical keyboards. They can achieve single-color or multi-color RGB lighting, and even support each key to light up independently, meeting the needs of gaming and personalization.

• Stabilizers - Installed under lager keys (such as the spacebar, Enter, and Shift), they are used to maintain the stability and balance of the keys.

Together, these parts constitute a complete keyboard assembly. It is precisely because of these components that the keyboard can operate stably, allowing every tap to be fed back to the computer quickly, accurately and comfortably.

About PCBasic

Time is money in your projects – and PCBasic gets it. PCBasic is a PCB assembly company that delivers fast, flawless results every time. Our comprehensive PCB assembly services include expert engineering support at every step, ensuring top quality in every board. As a leading PCB assembly manufacturer, we provide a one-stop solution that streamlines your supply chain. Partner with our advanced PCB prototype factory for quick turnarounds and superior results you can trust.

Mechanical vs. Membrane Keyboard PCBs

Not all keyboard PCBs are the same. The two most common categories are:

Key Factors to Consider When Buying a Keyboard PCB

When purchasing a keyboard PCB, the first thing to consider is its compatibility. Different users have different needs. Some people are accustomed to the ANSI layout, while others prefer the ISO. Common sizes such as 60% and 75% keyboard PCBs also directly affect the user experience.

Materials are equally important. There are many common materials on the market, but FR4 has always been regarded as the most reliable choice in terms of quality. It has high strength and good durability and is the standard for most mechanical keyboard PCBs.

Modern users have an increasingly higher demand for personalization, so programming support has also become a key point. Many DIY keyboard PCBs support QMK or VIA firmware, allowing users to freely program according to their personal habits and define shortcut keys or lighting effects.

In addition, the installation method of the keyboard PCB should also be taken into consideration. For beginners, the Hotswap PCB is a more user-friendly option. Users can replace the axles at any time without the need for soldering. However, if you are more in pursuit of stability and long-term use, a soldered PCB would be more suitable because it has a solid structure and is less likely to loosen.

Lighting effects are also a factor that many people pay attention to. Some people only need the basic monochrome backlight, while some players and enthusiasts prefer the custom keyboard PCB with RGB lighting effects, which can enable each key to light up independently and create a unique visual experience.

Finally, choosing a reliable manufacturer is extremely crucial. Manufacturers with a good reputation can provide stable product quality and more professional keyboard assembly services. Although a high-quality custom keyboard PCB may be more expensive, it often has a longer lifespan, better performance and greater flexibility. Finding the right balance between budget and functionality is the key to purchasing a keyboard PCB.

Choosing the Right Keyboard PCB and PCBA Manufacturer

PCBasic is dedicated to providing global customers with one-stop electronic manufacturing services of multiple varieties and small batches. Its core business covers PCB design and manufacturing, PCBA (SMT and DIP assembly), functional testing, and finished product assembly. It can not only produce common keyboard PCBs, but also provide customers with full-process support from prototype development to mass production, including custom keyboard PCB, 60% PCB, 75% keyboard PCB and Hotswap PCB.

In terms of manufacturing capabilities, PCBasic has multiple fully automatic SMT production lines, equipped with SPI solder paste inspection, AOI automatic optical inspection, X-Ray inspection, ICT online testing and functional testing platforms, ensuring that every keyboard circuit board meets high standards of reliability requirements. Meanwhile, it can provide a complete keyboard assembly service, from component soldering to the final product delivery, which is efficient and traceable throughout the process.

To ensure quality and international recognition, PCBasic has passed multiple authoritative certifications, including ISO 9001 Quality Management System, IATF 16949 Automotive Electronics Quality System, ISO 13485 Medical Electronics System, as well as environmental protection and safety certifications such as RoHS, CE, and FCC. These certificates not only reflect its pursuit of strict craftsmanship, but also ensure that PCBasic can provide stable and reliable keyboard PCB and PCBA services for customers in different fields.

Choosing PCBasic not only means choosing a manufacturer, but also finding a partner that can provide you with long-term cooperation, technical support and stable quality.

Conclusion

The keyboard PCB is the true core of every typing experience. Whether it's building a DIY keyboard PCB by yourself, upgrading to a more compact 60% keyboard PCB, or commissioning a complete keyboard assembly, it is very important to understand the details of keyboard PCB design.

From the common flexible PCB to the robust rigid PCB, from the convenient Hotswap PCB to the durable mechanical keyboard, the range of choices is very wide. Only by understanding the keyboard schematic, key components and the differences among various layouts can you select the appropriate solution for your keyboard projects, ensuring stable, customizable and durable input devices.