In the modern workspace and smart home ecosystem, the “last wire” is finally being cut. While standard Qi charging pads have been around for a decade, the conversation has shifted toward Long-Distance (Long-Range) Wireless Charging. Business owners, interior designers, and tech distributors are all asking the same question: How far can it actually reach, and is it ready for mass commercial use?
At Honghao Electronics, we specialize in the intersection of high-efficiency PCBA manufacturing and cutting-edge power solutions. In this comprehensive guide, we will explore the physics of distance, the current state of the industry, and how our technology is breaking the barriers of traditional charging.
1. The Physics of Distance: Why 10mm isn’t Enough
Traditional wireless charging (Magnetic Induction) requires almost perfect alignment and a distance of less than 8mm. This is why you have to place your phone on the pad.
However, Long-Distance Wireless Charging—often referred to as Under-Desk Charging—utilizes Magnetic Resonance or Long-Range Inductive Coupling.
The “Sweet Spot” in 2025
Currently, the industry standard for “long distance” in consumer electronics is categorized into three tiers:
Short Range (Standard Qi): 0mm – 8mm
Mid-Range (Through-surface): 10mm – 25mm
Long Range (Hidden/Under-desk): 25mm – 45mm
At Honghao Electronics, our flagship PCBA modules for under-desk chargers are optimized for the 20mm to 45mm range. This allows the charger to be mounted under a thick granite, wood, or glass tabletop, delivering power seamlessly through the material.
2. The Tech Behind the Reach: Magnetic Resonance vs. Induction
Why can some chargers reach 45mm while others fail at 10mm? It comes down to the PCBA design and Coil Quality.
Magnetic Resonance: The Distance King
Unlike simple induction, resonance allows the transmitter and receiver to “vibrate” at the same frequency. This enables:
Greater Z-height: Charging through thick surfaces.
Spatial Freedom: You don’t need to be centered to the millimeter.
Multi-Device Potential: Charging multiple low-power devices from one source.
Honghao’s Advantage: Precision PCBA Engineering
A long-distance charger is only as good as its circuit board. Our PCBA processing involves:
High-Q Factor Coils: We use custom-wound Litz wires that minimize skin effect and maximize energy transfer over distance.
Advanced MCU Integration: Our boards feature intelligent chips that auto-adjust frequency based on the surface thickness.
Thermal Management: Distance creates resistance. We utilize high-thermal conductivity substrates to ensure the charger stays cool even when pushing 15W through 40mm of solid oak.
3. Material Compatibility: What Can It Penetrate?
Distance is only one variable; the material is the other. To rank well on Google, we must address the most common user concerns regarding surface types.
| Material | Compatibility | Maximum Effective Distance |
| Wood (Oak, Walnut, Pine) | Excellent | Up to 45mm |
| Glass / Acrylic | Superior | Up to 50mm |
| Marble / Granite | Good (Watch for metal inclusions) | Up to 35mm |
| Metal (Steel, Aluminum) | Non-Compatible | 0mm (Induction creates heat) |
Pro Tip for B2B Buyers: When sourcing under-desk chargers, always ask for the FOD (Foreign Object Detection) sensitivity. Honghao’s PCBA designs include a multi-stage FOD algorithm that can distinguish between a phone’s internal battery and a stray coin on the table, ensuring maximum safety.
4. The Honghao Electronics Difference: From PCBA to Finished Product
We aren’t just a trading company; we are a technical powerhouse. Our history in PCBA processing gives us a unique edge in the wireless charging market.
Vertical Integration
Most suppliers buy “off-the-shelf” boards. We design, etch, and assemble our own.
SMT Excellence: Our surface-mount technology lines ensure that every capacitor and resistor is placed with aerospace-level precision.
PD Fast Charging Integration: We combine our Power Delivery (PD) expertise with wireless tech. Our chargers don’t just reach far; they charge fast (up to 15W/20W EPP standards).
Durability: Our PCBA modules are tested for over 10,000 hours of continuous load to ensure they won’t fail after a few months of use in a busy cafe or office.
5. Future Trends: How Far Will We Go?
Is 100mm possible? Is 1 meter possible?
In 2025, we are seeing the emergence of RF-based (Radio Frequency) wireless charging and Infrared-based power. However, for high-power devices like smartphones and tablets, Magnetic Resonance remains the only safe and efficient choice for the 20mm-50mm range.
The Rise of Qi2 and MagSafe
With the global adoption of Qi2, alignment is becoming easier. Honghao is already prototyping Qi2-Compatible Long-Distance Modules that use magnetic arrays to “lock” the phone into the optimal charging position from across the desk.
6. Why Choose Honghao Electronics for Your Next Project?
If you are looking to build a brand around under-desk chargers, multi-functional sockets, or high-speed PD adapters, you need a partner that understands the “guts” of the machine.
Customization (OEM/ODM): We can modify our PCBA layouts to fit your specific furniture or enclosure designs.
Global Certifications: Our products are designed to meet CE, FCC, and RoHS standards from the ground up.
Scale: With our advanced PCBA processing facility, we can scale from small batches to mass production without sacrificing quality.
Conclusion: Bridging the Gap
The limit of long-distance wireless charging isn’t just a number—it’s a balance of safety, efficiency, and material science. Currently, 45mm represents the “gold standard” for reliable, fast, and safe under-desk charging.
At Honghao Electronics, we are committed to pushing that boundary. Whether you need the PCBA components to build your own solution or a finished, market-ready long-range charger, we have the engineering expertise to make it happen.
Ready to Upgrade Your Product Line?
Don’t settle for “standard” when you can offer “extraordinary.” Contact Honghao Electronics today for a technical consultation on our PCBA services and wireless charging solutions.