Ferrite coil WL0243

EMIshieldedRF

Overview
Wireless charging coils are key components of inductive power transfer systems using electromagnetic induction to transfer energy between transmitter and receiver coils. Commonly used in consumer electronics (smartphones, smartwatches, tablets, earbuds), industrial control equipment and medical devices. Coils are wound with enameled copper wire into a flat spiral to provide low DC resistance, stable inductance, minimal heat and long service life. Ferrite shielding reduces EMI and improves transfer efficiency.

Features

• High magnetic efficiency from precisely wound enameled copper wire
• Stable inductance with ±5% tolerance options
• Low DC resistance (DCR) to limit power loss and heat
• Ferrite sheet shielding for EMI reduction and flux concentration
• Compact flat spiral form factor for small devices
• Customizable dimensions, wire gauge, inductance and terminals

Applications
Suitable for mobile devices (phones, tablets, wearables), wireless earbuds, in-car chargers, medical equipment requiring sealed/waterproof power transfer, industrial instruments and smart-home devices. They remove mechanical connectors and enable sealed enclosures.

Product Details
Electrical specifications

• Inductance (L): 300–500 µH
• Inductance tolerance: ±5%
• Test/operating frequency: commonly 85–205 kHz
• DC resistance (DCR): 80–250 mΩ
• Rated current (Irms): 1–3 A
• Quality factor (Q): ≥ 30
• Insulation resistance: ≥ 100 MΩ

Mechanical specifications

• Coil shape: round or square, flat spiral winding
• Wire type: enameled copper wire
• Shielding: ferrite sheet
• Insulation: PET or PI film
• Terminal type: solder pad or lead wire
• Mounting: adhesive fixing

Model dimensions (examples)

• WL35 — outer Ø 35 mm, inner Ø 15 mm, thickness 2.0 mm
• WL43 — outer Ø 43 mm, inner Ø 20 mm, thickness 2.0 mm
• WL50 — outer Ø 50 mm, inner Ø 25 mm, thickness 3.0 mm

Additional notes
Designs can be customized for wire diameter, inductance, shielding thickness and overall size to meet device constraints. Proper coil–controller matching, coil alignment and ferrite thickness affect charging efficiency and thermal behavior.

Technical specifications

• Inductance: typical range 300–500 µH
• Inductance tolerance: ±5%
• Operating frequency: 85–205 kHz
• DCR: ~80–250 mΩ
• Rated current: 1–3 A
• Quality factor: ≥ 30
• Insulation resistance: ≥ 100 MΩ