Pad de Încărcare Wireless (Qi, 15W, Fast Charge)

Qi2 vs Qi 1.x vs Profiluri Proprietare: Ce Înseamnă Diferența de Protocol pentru Produsul Dvs.

Qi2, released by the Wireless Power Consortium in 2023, introduces the Magnetic Power Profile (MPP) — a physical alignment ring that ensures the transmitter coil and receiver coil center within ±1mm. For the buyer, this matters in two ways: power delivery is predictably 15W without negotiation overhead, and the coil-to-coil coupling factor is high enough that thermal derating at the 15W ceiling is rare under normal use conditions. Qi 1.x EPP (Extended Power Profile) can also deliver 10–15W, but only through a proprietary authentication handshake — a Samsung charger delivering 15W to a Samsung phone is EPP with a private profile, not a standard anyone else can implement without a licensing agreement.

If your target market is iPhone 15 and later, Qi2 is the correct target. Apple requires MPP coil geometry (44mm outer, with the magnetic alignment ring at 51.6mm pitch circle diameter) and passes 15W only to devices that present a valid MPP handshake. A Qi 1.x pad will charge an iPhone 15 at 7.5W — but if your product is sold as a “fast wireless charger,” that 7.5W ceiling will generate negative reviews.

For Android-only or mixed-market products, Qi 1.x EPP at 10W covers most of the addressable market. The proprietary 15W profiles (Xiaomi, OPPO, Huawei, Samsung) require chipset licensing or white-label modules from the OEM’s approved supply chain — Chinese factories can supply these but only for specific brand ecosystems, not as a universal fast-charge pad.

The practical OEM decision: specify Qi2 for Apple-market products, Qi 1.x EPP + Samsung EPP for Android-primary products, and get explicit confirmation from the factory about which profiles their controller IC supports. Chips from Integrated Device Technology (IDT), Renesas, and NuVolta are common; verify the specific part number and its certified profile list before production.

FCC Partea 15 / Partea 18 și CE RED: Calea de Certificare și Ce Deține de Obicei Fabrica

Wireless charging pads emit intentional RF energy in the 100–205 kHz band (Qi operating frequency). This places them under FCC Part 18 (industrial, scientific, and medical equipment — unintentional and intentional radiators) and CE Radio Equipment Directive (RED) for European markets. The certification path is not identical to a simple EMC test.

FCC requirements. Part 18 requires a conducted and radiated emissions test at an accredited lab (A2LA or NVLAP). The test verifies that emissions outside the Qi operating band comply with the Part 18 limits. Additionally, Part 15 Subpart B applies to the digital circuitry inside the charger. Many Chinese factories hold an FCC ID on their reference design — if you are doing private-label with no hardware changes (different casing only), the factory’s existing FCC grant may be transferable via a Class II Permissive Change, which costs $500–1,500 and takes 4–8 weeks. If you change the coil geometry, the power IC, or the firmware, a new grant application is required ($3,000–6,000, 8–12 weeks at an independent lab).

CE RED and SAR. RED requires both EMC (ETSI EN 301 489-3) and radio performance testing. Qi pads also require evaluation against the SAR (Specific Absorption Rate) limits in EN 62311 — not because users hold the pad against their body, but because the regulation applies to any device with intentional RF emissions below 6 GHz. The test is straightforward for a flat pad, but the lab must conduct it, and the factory must provide a Declaration of Conformity referencing the specific test reports. If the factory provides only a CE mark on the device without a traceable DoC and test report set, that CE mark has no regulatory standing.

Our inspection service includes review of the certification documentation package — test reports, DoC, FCC grant letter — before shipment. A CE mark printed on a box is not compliance; the underlying paperwork is what matters at customs.

Calitatea Bobinării și Managementul Termic: Unde Pierderile de Eficiență Devin o Problemă de Produs

A wireless charger pad with poor coil winding or inadequate thermal design will charge phones slowly and run hot. Both are measurable at the factory before production commits. The key parameters to specify and verify:

Coil DC resistance (DCR). The transmitter coil’s copper resistance is the primary driver of I²R losses in the coil itself. A well-wound 44mm Qi2 transmitter coil in Litz wire should measure 300–500mΩ DCR at room temperature. Coils wound with insufficient strand count or inferior copper purity measure 600–900mΩ — directly adding 15–25% more heat generation at 15W load. Request the coil DCR measurement from the factory’s incoming quality control records.

Ferrite shielding thickness and grade. The ferrite layer beneath the coil redirects magnetic flux away from the device PCB and the USB-C port assembly. Under-thickness ferrite (less than 0.5mm in budget designs) causes eddy current losses in nearby metal and degrades efficiency. For a Qi2 15W pad, the ferrite shield should be NiZn or MnZn grade with permeability of 100–300 at 100kHz. This is a materials spec the factory should be able to confirm from their BOM.

Thermal path design. At 15W input and 87% efficiency, the pad dissipates approximately 2W internally. A pad with no thermal interface between the coil assembly and the outer casing will develop a hotspot on the charging surface exceeding 45°C under continuous load — above Qi2’s surface temperature specification and perceptibly warm to a user’s hand. Adequate designs use a thermally conductive pad (1–3 W/m·K) between the coil assembly and the bottom shell, which acts as a passive heat spreader. Some designs add a small aluminum baseplate. Verify this in the structural cross-section drawing before tooling sign-off.

Temperature-based power derating. Quality controller ICs implement a thermal foldback: if an NTC thermistor near the coil exceeds 60°C, output power steps down to 5W. This protects the device but will appear as “slow charging” to users in warm environments. Confirm the derating threshold and NTC placement with the factory’s hardware engineer, not just the sales contact. Our sourcing service can facilitate direct technical communication with the factory’s engineering team during the pre-production phase.

Domeniul de Personalizare OEM: Ce Poate Fi Schimbat Fără o Nouă Certificare

The range of customization available on a wireless charger pad varies significantly depending on whether you are using the factory’s certified reference design or starting from a clean-sheet BOM. Understanding the boundary prevents expensive surprises after tooling investment.

Casing and surface material — low risk. Changing the outer shell color, adding a logo, switching from ABS to PC/ABS, or adding a fabric surface wrap does not affect RF performance and does not require re-testing under most certification frameworks. It does require a Class II Permissive Change filing with the FCC if the FCC ID is being retained, which is straightforward. Aluminum top rings require more care: a closed metallic ring around the coil can affect coupling and may require EMC re-evaluation.

Coil diameter — moderate risk. Changing the coil from 44mm to 60mm (for desktop or multi-device pads) changes the antenna characteristics and requires new RF and efficiency testing. The factory should have validation data for common coil sizes; confirm before committing tooling.

Power delivery profile additions — high risk. Adding a proprietary fast-charge profile (e.g., 15W Samsung EPP or 50W Xiaomi wireless) requires chipset changes and new certification. This is not a minor modification. Budget for complete re-certification ($5,000–12,000 depending on the markets and profiles involved).

Cable and connector changes — low risk. Switching from USB-C to a fixed-cable design with a USB-A plug, or changing cable length, does not require RF re-testing. It may affect CE LVD evaluation if the input voltage changes, but cable modifications within the same input spec are typically covered by an updated Declaration of Conformity.

For buyers sourcing from consumer electronics factories in the Shenzhen area, the fastest path to a certified, private-label wireless pad is to select a factory with an existing Qi2 reference design, apply your branding to the casing, and do a Class II Permissive Change on the FCC filing. Total timeline from factory selection to certified production units: 10–16 weeks. Starting from a new design adds 12–20 weeks. See our guide on sourcing electronics from China for a broader overview of the sample-to-production timeline across electronics categories.