This Product Selection Guide contains information to help select products in the Wireless Charging Coils category on DigiKey.com
Wireless charging coils generate an alternating electromagnetic field used to inductively transfer energy to other coils positioned parallel and in close proximity. The energy is used to charge batteries or run the device receiving the energy. The coils may be designed as receivers, transmitters or dual purpose having single or multiple coils and multiple layers of windings. They are rated by their inductance, self-resonant frequency, saturation current and Q factor at a given frequency.
SelectionCharacteristics
Function: Indicates whether the device is a transmitter, receiver, or both.
Type: Indicates the number and pertinent construction details of the coil.
Inductance: Inductance indicates a device’s opposition to changes in the electrical current flowing through it. Measured in Henrys.
Tolerance: Characterizes the extent of permitted variability of overall device inductance among samples of a given part number, resulting from variations in manufacturing.
DC Resistance (DCR): Characterizes the maximum resistance of a current path through a device.
Q @ Freq: Characterizes the ratio of a device’s inductive reactance to its series resistance at the specified test frequency.
Current Rating (Amps): Typically this represents the maximum current to which a device will meet its given specifications. Exceeding this current may damage the device and/or other system components.
Current - Saturation (Isat): Characterizes device limitations imposed by magnetic constraints; the amount of DC bias current that results in inductance being reduced by some specified amount (often 20-30%) from its zero-bias value.
Frequency - Self Resonant: The frequency above which the effect of an inductor’s parasitic capacitances become dominant, and the device behaves in a capacitive manner.
Operating Temperature: Recommended operating temperature, typically given in a range or as a maximum. Exceeding these temperatures may affect performance or damage the device and other system components.
Size/Dimension: The physical dimensions of the device. Typically diameter and height or length, width, and height.
ProductExamples
| MFR PART # | WT1005690-12K2-A6-G |
|---|---|
| DIGIKEY PART # | 445-16096-ND |
| MANUFACTURER | TDK Corporation |
| DESCRIPTION | TX 3 COIL 1 LAYER 11.5 - 12.5UH |
| DATASHEET | Click Here |
| MFR PART # | WR483245-15F5-G |
|---|---|
| DIGIKEY PART # | 445-16091-ND |
| MANUFACTURER | TDK Corporation |
| DESCRIPTION | RX 1 COIL 1 LYR 13UH |
| DATASHEET | Click Here |
SchematicSymbol
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MediaLinks
Videos
EYE on NPI: TDK WCT Ultrathin Pattern Coil for Wireless Charging
Wireless Power Transfer Advanced Coil Knowledge – We Cut the Cord!
ROHM BD570xx Qi Wireless Power ICs
Articles
The Future of Wireless Charging
Qi Compliant Wireless Charging
Use Wireless Power to Improve Convenience for Wearables
Inductive Versus Resonant Wireless Charging
Blogs
Wireless Charging is Coming of Age
Wireless Charging: Seamlessly Sending Power Over the Air
Product Training Modules
Wireless Charging Coils
TechForum
Q Value of an Inductor (Coil)