south-facing pcb

What Is South-Facing PCB? South-Facing PCB vs North-Facing PCB

Tuesday, May 12th, 2026

What Is South-Facing PCB?

What is south-facing PCB? A south-facing PCB is a mechanical keyboard PCB layout where the switch LED opening or switch orientation faces the lower side of the keyboard, usually toward the spacebar and the user. In keyboard language, “south” simply means the bottom direction of the board.

This term is mainly used in custom mechanical keyboards. It does not describe the geographic direction of the PCB. Instead, it explains how the switch and LED are positioned on the circuit board.

South-facing PCB layouts are popular because they work well with many custom keycaps, especially Cherry Profile keycaps. They are often chosen by keyboard enthusiasts who care about typing feel, sound, and keycap flexibility.

South-Facing PCB vs North-Facing PCB

South-facing PCB and north-facing PCB mainly differ in switch LED position, keycap compatibility, RGB brightness, and typing feel. South-facing PCB is often better for Cherry Profile keycaps and custom builds, while north-facing PCB is usually better for bright RGB shine-through legends.

A north-facing PCB places the LED closer to the top side of the keycap. Since many shine-through keycaps have legends near the upper part of the keycap, the light can pass through the letters more directly. This is why many gaming keyboards use north-facing LEDs.

A south-facing PCB places the LED closer to the lower side of the keycap. This layout may produce softer lighting, but it usually improves keycap compatibility. It is common in custom mechanical keyboards because users often install aftermarket keycap sets.

If you want a keyboard mainly for typing, custom keycaps, or a refined sound profile, south-facing PCB is usually more attractive. If you want strong RGB shine-through letters, north-facing PCB may be more suitable.

Is South-Facing PCB Better?

South-facing PCB is better for many custom mechanical keyboard users, especially those who use Cherry Profile keycaps or thick PBT keycaps. However, it is not automatically better for every keyboard. The better choice depends on your keycaps, RGB preference, and typing needs.

For custom keyboard users, south-facing PCB has a strong advantage because it gives more freedom. You can change keycap sets more easily. You can use many popular profiles without worrying as much about switch housing interference. This makes the keyboard more upgrade-friendly.

South-facing PCB is usually better when you care about:

Cherry Profile keycap compatibility
Smooth key travel
Custom keycap support
PBT keycap sets
Typing sound consistency
Long-term keyboard modification
Enthusiast-style keyboard builds

North-facing PCB can still be better when you care about:

Bright RGB legends
Gaming keyboard appearance
Shine-through ABS keycaps
Strong lighting through letters and symbols
Factory-style RGB visual effects

The best way to choose is to think about your priority. If your priority is typing feel and keycap freedom, south-facing PCB is usually better. If your priority is bright RGB through keycap legends, north-facing PCB may be better.

Does South-Facing PCB Affect RGB Lighting?

Yes, south-facing PCB affects RGB lighting because the LED is positioned toward the lower side of the switch. The RGB still works, but the light may not shine through top legends as directly as it does on a north-facing PCB.

This is one of the most important things to understand before buying a keyboard. South-facing PCB does not mean the keyboard has weak lighting. It means the light direction is different.

If you use opaque PBT keycaps, the difference may not matter much. The light will mostly appear around the switch area, under the keycap, or between the keys. This can create a softer and cleaner glow.

If you use shine-through keycaps with letters on the upper part, north-facing PCB usually makes those letters brighter. The LED sits closer to the legend, so the light passes through more directly.

Does South-Facing PCB Work with Cherry Profile Keycaps?

Yes, south-facing PCB works very well with Cherry Profile keycaps. In fact, Cherry Profile compatibility is one of the biggest reasons many custom keyboards use south-facing PCB layouts.

Cherry Profile keycaps are popular because they are comfortable, clean, and not too tall. Many premium keycap sets use this profile. However, because of their lower height and inner shape, some Cherry Profile keycaps may interfere with north-facing switch housings.

Keycap interference means the inside of the keycap may touch part of the switch housing during a keypress. This can make the key feel less smooth. It may also affect sound because the keycap does not move as freely as expected.

South-facing PCB helps reduce this issue because the switch orientation changes the contact relationship between the keycap and the switch housing.

How to Tell If a Keyboard Has a South-Facing PCB?

You can tell if a keyboard has a south-facing PCB by checking the LED position under the keycap. If the LED window is below the switch stem and closer to the spacebar side, the keyboard likely uses a south-facing PCB.

The easiest way is to remove one keycap carefully and look at the switch. On many mechanical switches, there is a small transparent window, LED slot, or opening. Its direction tells you whether the PCB is south-facing or north-facing.

You can also check the product page. Many keyboard brands mention this feature because it matters to custom keyboard users. Look for phrases such as:

South-facing PCB
South-facing LEDs
South-facing RGB
Cherry Profile compatible
No north-facing interference
Custom keycap friendly
Hot-swappable south-facing sockets

How to Tell If a Keyboard Has a South-Facing PCB?

South-Facing PCB for Mechanical Keyboard

South-facing PCB is widely used in mechanical keyboards, especially in custom keyboard kits and enthusiast-grade designs. It supports better keycap compatibility and gives users more freedom to modify the keyboard after purchase.

Mechanical keyboards are different from ordinary office keyboards because users often change parts. They may replace switches, install new keycaps, tune stabilizers, add foam, or rebuild the keyboard for a different sound. In this type of product, PCB orientation becomes important.

A south-facing PCB can be used in many keyboard layouts, including:

60% keyboard
65% keyboard
75% keyboard
TKL keyboard
Full-size mechanical keyboard
Split keyboard
Hot-swappable keyboard
Soldered custom keyboard

For hot-swappable mechanical keyboards, the PCB design must match the socket direction correctly. The socket pads need enough strength because users may replace switches many times. Good pad design helps prevent lifting, cracking, or poor contact.

Are South-Facing Switches Real?

The phrase “south-facing switches” is commonly used, but it is not the most accurate technical term. In most cases, people actually mean south-facing PCB or south-facing switch orientation.

A mechanical switch itself is not permanently south-facing or north-facing. The switch becomes south-facing when it is installed into a PCB layout that positions it in that direction.

For example, the same MX-style switch could be installed in different orientations if the PCB footprint allows it. The switch model does not change, while PCB design decides the final direction.

This is why users should focus on the keyboard PCB specification, not only the switch name.

Should You Choose South-Facing or North-Facing PCB?

You should choose south-facing PCB if you care more about keycap compatibility, Cherry Profile support, and typing feel. You should choose north-facing PCB if you care more about bright RGB legends and shine-through lighting. Here is a simple final decision guide:

Choose south-facing PCB if you want:

Better Cherry Profile compatibility
More keycap freedom
A custom keyboard feel
Less risk of keycap interference
A cleaner long-term upgrade path

Choose north-facing PCB if you want:

Brighter RGB legends
Stronger gaming-style lighting
Better shine-through keycap performance
A keyboard mainly used for visual effects

For most users interested in custom mechanical keyboards, south-facing PCB is the safer and more flexible option. For users who strongly prefer bright RGB letters, north-facing PCB is still a practical choice.

FAQs

1. What is south-facing PCB in a keyboard?
A south-facing PCB is a keyboard PCB layout where the switch LED opening or switch orientation faces the lower side of the keyboard, toward the spacebar. It is common in custom mechanical keyboards because it improves compatibility with many keycap profiles.

2. Is south-facing PCB better than north-facing PCB?
South-facing PCB is usually better for keycap compatibility and Cherry Profile keycaps. North-facing PCB is usually better for bright shine-through RGB legends. The better option depends on whether you care more about typing feel or lighting.

3. Does south-facing PCB have RGB?
Yes, a south-facing PCB can still have RGB lighting. The difference is the LED direction. The light may appear softer or less direct through top legends, but it can still create a good under-key glow.

4. Why do custom keyboards use south-facing PCB?
Custom keyboards often use south-facing PCB because users like changing keycaps. South-facing layouts usually support more keycap profiles and reduce the chance of Cherry Profile interference.

5. Does south-facing PCB work with Cherry Profile keycaps?
Yes, south-facing PCB works very well with Cherry Profile keycaps. It is often recommended for users who plan to install Cherry Profile sets because it can help avoid keycap and switch housing contact.

6. How do I know if my keyboard is south-facing?
Remove a keycap and check the LED position. If the LED window is closer to the lower side of the keyboard, near the spacebar direction, it is likely south-facing. You can also check the product page for “south-facing PCB” or “south-facing LEDs.”

7. Are south-facing switches different from normal switches?
Usually no. The switch itself is normally a standard mechanical switch. The PCB layout decides whether the switch is installed in a south-facing or north-facing direction.

8. Is south-facing PCB good for gaming?
Yes, south-facing PCB can be good for gaming, especially if you care about keycap compatibility and typing comfort. However, if your main goal is bright RGB legends, north-facing PCB may be more suitable.

9. Can hot-swappable keyboards use south-facing PCB?
Yes. Many hot-swappable custom keyboards use south-facing PCB layouts. The hot-swap socket simply needs to be designed in the correct orientation.

10. Should beginners choose south-facing PCB?
Beginners who plan to try different keycaps should consider south-facing PCB. It offers more flexibility and reduces common compatibility concerns. Beginners who mainly want bright RGB letters may prefer north-facing PCB.

Conclusion

South-facing PCB is a popular mechanical keyboard PCB layout where the switch LED or switch orientation faces the lower side of the keyboard. It is widely used in custom keyboards because it supports better keycap compatibility, especially with Cherry Profile keycaps.

Compared with north-facing PCB, south-facing PCB is usually better for typing feel, keycap freedom, and long-term customization. North-facing PCB remains useful for users who want bright RGB shine-through legends.

The best choice is not about following a trend. It is about matching the PCB layout with your real keyboard needs. If you want a custom-friendly keyboard with more keycap options, south-facing PCB is usually the better path. If you want strong RGB letters for a gaming setup, north-facing PCB can still be a strong choice.

What Is a South-Facing PCB and How Does It Work?

A south-facing PCB is defined by its switch mounting orientation: the LED aperture on each switch socket faces the bottom edge of the PCB. When switches are soldered or hot-swapped onto the board, this orientation positions the LED below the keycap rather than above it. This setup avoids interference with Cherry-profile keycaps—one of the most popular keycap designs—preventing the keycap stem from colliding with the LED. The PCB’s trace routing and pad placement are optimized to support this orientation, ensuring stable electrical connections and compatibility with standard switch footprints.

South-Facing vs. North-Facing PCB: What’s the Difference?

Feature	South-Facing PCB	North-Facing PCB
LED Orientation	Faces bottom of PCB (toward user)	Faces top of PCB (away from user)
Keycap Compatibility	Works with all profiles (no Cherry profile interference)	Cherry profile keycaps may collide with LEDs
RGB Lighting Performance	Dimmer legend backlighting; better side glow	Brighter legend backlighting; direct LED alignment
Typical Applications	Custom keyboards, industrial control panels	Gaming keyboards, RGB-focused devices
Switch Compatibility	Supports all standard MX-style switches	Same switch compatibility; LED position varies

What Are the Advantages of a South-Facing PCB?

Keycap Versatility

The primary advantage of a south-facing PCB is universal keycap compatibility. It eliminates interference with Cherry, OEM, and DSA profiles, allowing users to customize their devices without fit issues. This is critical for custom keyboard builders and industrial equipment designers who require specific keycap ergonomics.

Stable Typing Experience

By avoiding keycap-stem collisions, south-facing PCBs deliver a smoother typing feel with consistent switch actuation. This stability is essential for medical devices like diagnostic equipment, where precise input is non-negotiable.

Design Flexibility

South-facing PCBs support hot-swappable and soldered switch configurations, offering flexibility for prototyping and production. This adaptability makes them suitable for aerospace components, where design iterations and reliability are paramount.

What Industries Use South-Facing PCBs?

Medical Equipment

Medical devices like patient monitors and diagnostic keyboards rely on south-facing PCBs for reliable input and keycap compatibility. A leading medical equipment manufacturer integrated our south-facing PCB into their portable ultrasound machines, ensuring clinicians can use sterile, custom keycaps without performance issues.

Aerospace

Aerospace control panels use south-facing PCBs for their durability and design flexibility. Our south-facing PCB was adopted in a commercial aircraft’s in-flight entertainment system, supporting rugged keycaps and stable operation in extreme pressure and temperature conditions.

Industrial Equipment

Industrial control terminals and machinery interfaces benefit from south-facing PCBs’ keycap versatility. A manufacturing client used our PCBs in assembly line control panels, allowing workers to use wear-resistant keycaps without interfering with switch functionality.

How to Design a South-Facing PCB for Optimal Performance?

Start by selecting switch footprints compatible with south-facing orientation (MX-style is standard). Ensure LED pads are positioned at the bottom of each switch socket, with trace routing that avoids signal interference. Incorporate ground planes to enhance signal integrity, critical for high-speed industrial and aerospace applications. Conduct design rule checks (DRC) to verify pad spacing and prevent short circuits, and test with sample keycaps to confirm no interference.

Use 1oz-2oz copper for traces to support current demands
Position LEDs 0.5mm below switch stems to avoid contact
Integrate ESD protection for sensitive electronic environments

Common Issues with South-Facing PCBs and How to Fix Them?

Dim RGB Lighting

South-facing LEDs produce dimmer legend backlighting. Fix this by using high-brightness LEDs (3000mcd+) or dye-sublimated keycaps with translucent legends. For industrial devices, prioritize side glow over legend lighting if backlighting is non-essential.

Switch Installation Misalignment

Misaligned switches cause keycap wobble. Ensure PCB pads are precision-drilled (tolerance ±0.05mm) and use alignment jigs during assembly. This is critical for medical devices where input precision is critical.

Signal Interference

Poor trace routing leads to signal degradation. Use ground planes and separate analog/digital traces to minimize interference. For aerospace applications, conduct EMI testing to ensure compliance with industry standards.

FAQ About South-Facing PCBs

Can south-facing PCBs use north-facing switches? No—switches are orientation-agnostic, but the PCB’s LED pad position determines compatibility. South-facing PCBs work with standard MX-style switches; only the LED aperture direction differs.

Do south-facing PCBs support hot-swappable switches? Yes—many south-facing PCBs feature hot-swap sockets (e.g., Kailh) for tool-free switch replacement. This is ideal for custom keyboards and industrial prototyping.

Are south-facing PCBs more expensive than north-facing ones? No—cost is comparable, as the only difference is pad and LED placement. Pricing depends on materials (e.g., FR-4 vs. high-temperature substrates) and manufacturing complexity.

Can south-facing PCBs be used for gaming keyboards? Yes—though RGB performance is dimmer, gamers prioritizing keycap customization over bright backlighting prefer them. Some gaming keyboards use south-facing designs for Cherry profile compatibility.

How to test a south-facing PCB for LED functionality? Use a multimeter to check continuity between LED pads and traces. Power the PCB with a 5V source and verify LED illumination; dim legends are normal for south-facing orientations.

Are south-facing PCBs suitable for high-temperature environments? Yes—when manufactured with high-temperature substrates (e.g., polyimide), they perform reliably in aerospace and industrial settings with temperatures up to 150°C.

What Materials Are Best for South-Facing PCBs?

For most applications, FR-4 is the standard substrate due to its durability and cost-effectiveness. For medical and aerospace devices, use high-reliability materials like Rogers 4003C (for high-frequency signals) or polyimide (for flexibility and temperature resistance). Copper thickness (1oz-2oz) should match current demands, and solder mask in green or black ensures corrosion resistance.

How to Choose the Right South-Facing PCB for Your Project?

Consider your application’s needs: keycap compatibility (Cherry profile users need south-facing), lighting requirements (RGB vs. non-RGB), and environmental conditions (temperature, moisture). For industrial and medical projects, prioritize PCBs with ISO 13485 or IPC-6012 certification. Partner with a manufacturer that offers custom routing to match your switch layout and component placement.

What Are the Best Practices for Assembling South-Facing PCBs?

Use lead-free solder (Sn96.5/Ag3.0/Cu0.5) for compliance with industrial standards. Avoid overheating switches during soldering (temperature ≤350°C, time ≤3 seconds) to prevent LED damage. Test keycap fit before final assembly to ensure no interference, and conduct continuity checks for all traces and LEDs. For hot-swappable PCBs, verify socket alignment to prevent switch wobble.

How Does ESD Protection Impact South-Facing PCBs?

Electrostatic discharge (ESD) can damage LEDs and switches on south-facing PCBs. Integrate ESD diodes (e.g., TVS diodes) near LED pads and switch sockets. For medical and aerospace applications, ensure surface resistance between 10⁶-10⁹Ω to dissipate static. Use conductive packaging during storage and assembly to prevent ESD-related failures.

What Trends Are Shaping South-Facing PCB Design?

Increased demand for custom mechanical keyboards drives innovations in south-facing PCB design, including hot-swappable sockets and integrated RGB controllers. Medical and aerospace industries are adopting smaller, more durable south-facing PCBs for portable devices. Advances in LED technology (micro-LEDs) are improving backlighting performance, addressing the dimness issue associated with south-facing orientations.

At EBest, we specialize in high-quality south-facing PCB manufacturing for medical, aerospace, and industrial applications. Our south-facing PCB products meet strict E-E-A-T standards, with custom design support for south-facing pcb design and tailored solutions for aerospace south-facing pcb and medical device south-facing pcb requirements. We also provide expert guidance for south-facing pcb assembly best practices and high-performance options for south-facing pcb for industrial equipment. Whether you need prototype batches or mass production, we deliver reliable, compatible south-facing PCBs tailored to your unique project needs. Contact us at sales@bestpcbs.com to place your order today.