Wireless Charging Coils

238 Wireless Charging Coils from 10 manufacturers listed on everything RF

Wireless Charging Coils from the leading manufacturers listed here. Find coils for wireless charging applications based on their inductance, configuration, Q Factor and a number of other parameters.

Description:20 Qi Wireless Charging Coil with 1.6 to 7.8 µH Inductance
Configuration:
Receiving Coil
Standard:
Qi
Inductance:
1.6 to 7.8 µH
SRF:
22 to 24 MHz
DCR:
80 to 340 mOhms
Q Factor:
19 to 47
more info
Description:25 MOhms, WPC Transmitter Coil
Configuration:
Transmitter Coil
Standard:
WPC
Inductance:
7 uH
DCR:
25 mOhms
more info
Description:72 mOhms, 24 μH Receiving / Transmitter Coil
Configuration:
Receiving Coil, Transmitter Coil
Standard:
Qi
Inductance:
24 µH
SRF:
2.8 MHz
DCR:
72 mOhms
Q Factor:
170
more info
Description:5 W Receiving Coil with 13 µH Inductance
Configuration:
Receiving Coil
Standard:
WPC
Inductance:
13 µH
DCR:
270 mOhms
Voltage:
4.95 to 5.05 V
more info
Description:5 W, WPC / Qi Transmitter Coil with 10.35 to 13.75 uH Inductance
Configuration:
Transmitter Coil
Standard:
WPC, Qi
Inductance:
10.35 to 13.75 uH
DCR:
80 mOHms
more info
Description:187 mOhms Receiving Coil with 10.8 uH Inductance
Configuration:
Receiving Coil
Standard:
Qi
Inductance:
10.8 uH
DCR:
187 mOhms
Q Factor:
60
more info
Description:PowerLife Wireless Charging Coil, Receive, High Frequency, Wearable
Inductance:
4 uH
DCR:
235 mOhms
more info
Description:15 W Qi Wireless Charging Coil with 6.4 to 6.9 µH Inductance
Standard:
Qi
Inductance:
6.4 to 6.9 µH
SRF:
15 MHz
DCR:
38 to 45 mOhms
Q Factor:
100
more info
Description:25 MOhms, WPC Transmitter Coil
Configuration:
Transmitter Coil
Standard:
WPC
Inductance:
6.3 uH
DCR:
25 mOhms
more info
Description:160 mOhms, 10 μH Receiving Coil
Configuration:
Receiving Coil
Standard:
Qi
Inductance:
10 µH
DCR:
160 mOhms
Q Factor:
38
more info

What are Wireless Charging Coils?

Wireless charging coils are the coils used to wirelessly transmit and receiver power. These coils are made of copper. There are two coils required by a wireless charging system - a transmitter coil in the charging pad and a receiver coil in the device that needs to be charged. Coils which can perform both transmission and reception are also available.

An alternating current passed through the transmitter coil creates an oscillating magnetic field which fluctuates in strength as the electric current’s amplitude fluctuates. When a receiver coil is placed near the transmitter coil, the changing magnetic field induces an alternating electric current in it. This induced current is passed through a rectifier to convert it to direct current that can charge the device’s battery. Capacitors are added to both coils so that they resonate at the same frequency i.e. the frequency of the alternating current. Doing this increases the amount of induced current in the receiver coil thus improves the efficiency of power transmission.

 

These coils are generally used for low power applications usually from 5 to 15 W for consumer electronics such as smartphones, handheld devices. For higher power applications like electric vehicle charging etc. which requires power over 1 kilowatt, bigger and more coils are used. Coil size also affects the distance of power transfer. The bigger the coil, or the more coils there are, the greater the distance a charge can travel. In the case of small handheld devices like smartphones, smart home devices, wireless charging pads etc. the copper coils are only a few inches in diameter, severely limiting the distance over which power can travel efficiently. As higher power applications use bigger and more coils, power can be transmitted at distances of up to a couple of meters.

Qi is the wireless charging standard maintained by the Wireless Power Consortium (WPC) for powering devices in the range of 5-65 W. It states specifications like power regulation with a digital control loop and coil dimensions of 5mm to 40 mm. Qi specification is the most popular standard in the world, with more than 200 million devices supporting this interface. For higher power applications Magne charge, SAE J2954, AirFuel Alliance etc. are some examples of standards currently being used.