Ferrite shield located intermediate a wireless power transmitter and receiver and method of using same
An adapter device is configured to interface between a wireless power receiver that includes a first array of magnets arranged around a receiver coil in the wireless power receiver and a wireless power transmitter lacking a corresponding array of magnets arranged around a source coil in the wireless power transmitter. The adapter device includes a substrate and a ferrite shield formed of a magnetic material and configured to be placed between the wireless power receiver and the wireless power transmitter.
1. An adapter device configured to interface with a wireless power transmitter having a first magnetic shield surrounding a source coil, the adapter device comprising:
a substrate; and
a ferrite shield formed of a magnetic material; and
a second magnetic shield embedded in the substrate in a location proximate to the ferrite shield and arranged coaxially with the ferrite shield.
2. The adapter device according to claim 1 , wherein the substrate is a planar substrate formed of a dielectric material.
3. The adapter device of claim 1 , wherein the ferrite shield at least partially overlaps with the source coil.
4. The adapter device according to claim 1 , wherein the ferrite shield has an annular shape.
5. The adapter device according to claim 1 , wherein the second magnetic shield extends laterally beyond the first magnetic shield.
6. A method of interfacing with a wireless power transmitter having a first magnetic shield surrounding a source coil, comprising:
providing an adapter device having a planar substrate, a ferrite shield embedded within the planar substrate, and a second magnetic shield embedded within the planar substrate;
locating the second magnetic shield proximate to the ferrite shield; and
arranging the second magnetic shield coaxially with the ferrite shield.
7. The method according to claim 6 , wherein the planar substrate is formed of a dielectric material.
8. The method according to claim 7 , further comprising attaching the adapter device to the wireless power transmitter.
9. The method according to claim 6 , wherein the ferrite shield has an annular shape.
10. The method according to claim 6 , wherein the second magnetic shield extends laterally beyond the first magnetic shield.
11. A wireless power charging device comprising:
a wireless power transmitter having a first magnetic shield surrounding a plurality of source coils; and
an adapter device to interface with the wireless power transmitter, the adapter device comprising:
a substrate; and
a ferrite shield embedded in the substrate, the ferrite shield positioned to overlap with at least some of the plurality of source coils; and
a second magnetic shield embedded in the substrate in a location proximate to the ferrite shield and arranged coaxially with the ferrite shield.
12. The wireless power charging device of claim 11 , wherein the substrate is a planar substrate formed of a dielectric material.
13. The wireless power charging device of claim 11 , wherein the ferrite shield has an annular shape.
14. The wireless power charging device of claim 11 , wherein the second magnetic shield extends laterally beyond the first magnetic shield.