Electronic device with coil for wireless charging and haptic outputs

1. An electronic watch comprising:

a housing at least partially defining an internal volume and comprising a dielectric member defining a charging surface along a back side of the electronic watch, the charging surface configured to contact an external charging device during a battery charging operation;

a display positioned at least partially within the housing;

a transparent cover coupled to the housing and at least partially covering the display;

a battery;

a magnet positioned within the internal volume, the magnet movable relative to the housing and configured to magnetically align the housing relative to the external charging device during the battery charging operation; and

a stationary coil conductively coupled to the battery and comprising multiple conductive windings, the stationary coil configured to:

during the battery charging operation, supply a first current to the battery from a first grouping of the multiple conductive windings; and

during a haptic output operation, receive a second current from the battery at a second grouping of the multiple conductive windings to move the magnet, thereby producing a haptic output, the second grouping of conductive windings different from the first grouping of conductive windings.

2. The electronic watch of claim 1 , wherein:

the stationary coil is configured to inductively couple to an output coil of the external charging device during the battery charging operation;

the second current causes the stationary coil to produce a magnetic field; and

the haptic output is produced as a result of an interaction between the magnetic field and the magnet that causes the magnet to move relative to the housing.

3. The electronic watch of claim 2 , wherein the magnet is movably coupled to the housing via a compliant member.

4. The electronic watch of claim 1 , wherein:

the housing comprises:

a first housing member defining a first exterior surface of the housing; and

a second housing member defining a second exterior surface of the housing configured to contact a user when the electronic watch is being worn.

5. The electronic watch of claim 4 , wherein:

the transparent cover defines a front surface of the electronic watch; and

the second housing member defines at least a portion of a rear surface of the electronic watch, the rear surface opposite the front surface.

6. The electronic watch of claim 1 , wherein the stationary coil is configured to produce the first current as a result of a wireless power transfer from the external charging device to the stationary coil.

7. The electronic watch of claim 1 , further comprising a retention system configured to constrain movement of the magnet during the battery charging operation.

8. The electronic watch of claim 1 , wherein the magnet is a ring-shaped magnet.

9. The electronic watch of claim 1 , wherein the magnet is positioned in a central area defined by the stationary coil.

10. The electronic watch of claim 1 , wherein the second grouping of the multiple conductive windings comprises more windings than the first grouping of the multiple conductive windings.

11. An electronic device comprising:

a housing comprising a dielectric material defining an exterior surface of the electronic device, the exterior surface configured to contact an external power source during a charging operation;

a battery positioned at least partially within the housing;

a stationary coil positioned at least partially within the housing and comprising multiple conductive windings; and

a movable magnet positioned at least partially within the housing and configured to magnetically align the electronic device relative to the external power source, wherein:

in a first mode of operation, a first grouping of the multiple conductive windings of the stationary coil wirelessly receives power from the external power source, the received power being provided to the battery; and

in a second mode of operation, a second grouping of the multiple conductive windings of the stationary coil receives a drive signal, thereby causing the movable magnet to move and produce a haptic output along the exterior surface of the housing, the second grouping different from the first grouping.

12. The electronic device of claim 11 , wherein:

the electronic device is a stylus comprising:

an elongate housing defining a first end and a second end and defining an internal cavity;

a tip positioned at the second end of the elongate housing and configured to provide input to an additional electronic device; and

the exterior surface is a side surface of the elongate housing.

13. The electronic device of claim 11 , wherein:

the electronic device is a watch comprising:

a display positioned at least partially within the housing and configured to display a graphical output;

a transparent cover positioned over the display; and

a touch sensor positioned below the transparent cover and configured to detect a touch input applied to the transparent cover;

the housing defines a rear wall along a rear side that is opposite to the transparent cover, the rear wall comprising the dielectric material; and

the first grouping of the multiple conductive windings coil is configured to inductively couple to an output coil through the dielectric material when the electronic device is in the first mode of operation.

14. The electronic device of claim 11 , wherein:

in the second mode of operation, the drive signal causes a current to pass through the second grouping of the multiple conductive windings coil; and

the second grouping of the multiple conductive windings coil causes the movable magnet to move as a result of an interaction between a magnetic field produced by the movable magnet and Lorentz forces acting on the second grouping of the multiple conductive windings.

15. The electronic device of claim 11 , wherein:

the movable magnet is coupled to the housing via a compliant member that allows the movable magnet to move relative to the housing; and

the electronic device further comprises a retention system configured to constrain movement of the movable magnet when the electronic device is in the first mode of operation.

16. The electronic device of claim 11 , wherein:

the stationary coil comprises two coil segments conductive windings; and

the electronic device further comprises a switching circuit configured to:

conductively couple the two coil segments during the second mode of operation; and

conductively decouple the two coil segments during the first mode of operation.

17. The electronic device of claim 11 , wherein:

the stationary coil comprises multiple turns of a wire wrapped about a central area; and

the movable magnet is positioned at least partially within the central area.

18. An electronic device comprising:

a housing comprising a dielectric member defining a charging surface along a back side of the electronic device;

a display positioned at least partially within the housing;

a transparent cover positioned over the display and defining a front surface of the electronic device;

a battery positioned at least partially within the housing;

a magnet positioned within the housing, the magnet movable relative to the housing and configured to magnetically align the housing relative to an external charging device during a battery charging operation; and

a stationary coil positioned at least partially within the housing and comprising multiple conductive windings, the stationary coil configured to:

produce, using a first grouping of the multiple conductive windings, a current when the first grouping of the multiple conductive windings is inductively coupled to an output coil of the external charging device through the dielectric member, the current being used to charge the battery; and

produce, using a second grouping of the multiple conductive windings different from the first grouping of the multiple conductive windings, a magnetic field when the second grouping of the multiple conductive windings is supplied with a current from the battery, the magnetic field configured to cause the magnet to move within the housing, thereby producing a haptic output detectable along an exterior surface of the electronic device.

19. The electronic device of claim 18 , further comprising a retention system configured to:

secure the magnet when the coil first grouping of the multiple conductive windings is inductively coupled to the output coil; and

release the magnet when the second grouping of the multiple conductive windings is supplied with the current from the battery to produce the haptic output.

20. The electronic device of claim 18 , wherein the housing comprises a metal housing member coupled to the dielectric member and defining a side surface of the electronic device.