Proximity detection for an input mechanism of an electronic device

1. A wearable electronic device, comprising:

a rotatable crown, electrically connected to a shaft;

a housing, electrically isolated from the rotatable crown and the shaft; and

a proximity sensing component operative to determine when an object exterior to the wearable electronic device is in proximity to the rotatable crown,

wherein:

the housing acts as a first electrode of the proximity sensing component and is electrically connected to the proximity sensing component;

the rotatable crown and the shaft act as a second electrode of the proximity sensing component, the shaft is electrically connected to the proximity sensing component, and the shaft extends through an opening in the housing; and

the proximity sensing component is configured to determine a proximity of the object to the rotatable crown based on a change in a capacitance between the housing and the rotatable crown.

2. The wearable electronic device of claim 1 , wherein the proximity sensing component is part of a display stack contained within the housing.

3. The wearable electronic device of claim 1 , wherein the proximity sensing component is integrated with a force sensing device.

4. The wearable electronic device of claim 1 , wherein the housing is electrically isolated from the rotatable crown by at least one insert separating the housing and the rotatable crown.

5. The wearable electronic device of claim 4 , wherein the at least one insert supports the shaft of the rotatable crown.

6. The wearable electronic device of claim 1 , wherein the proximity sensing component is configured to indicate the object is proximate to the rotatable crown when the change in capacitance exceeds a capacitance change threshold.

7. The wearable electronic device of claim 6 , wherein the proximity sensing component triggers a change in a state of the wearable electronic device when the change in capacitance exceeds the capacitance change threshold.

8. A wearable electronic device, comprising:

a proximity sensor operative to determine when an object exterior to the wearable electronic device is in proximity to at least a portion of the wearable electronic device;

an input mechanism having an exterior contact surface that is electrically connected to the proximity sensor and acts as a first electrode of the proximity sensor; and

a housing of the wearable electronic device that is electrically connected to the proximity sensor and acts as a second electrical component electrode of the proximity sensor,

wherein:

the housing is electrically isolated from the input mechanism;

the input mechanism extends through an opening in the housing;

the input mechanism is operable to be moved in a direction toward the housing; and

the proximity sensor is configured to determine when the object is in proximity to the input mechanism based on a change in a capacitance between the housing and the input mechanism.

9. The wearable electronic device of claim 8 , wherein the input mechanism is a rotatable crown.

10. The wearable electronic device of claim 8 , wherein the housing comprises an insert that electrically isolates the input mechanism and the housing.

11. The wearable electronic device of claim 10 , wherein the insert is one of plastic, ceramic, or rubber.

12. A method for determining proximity of an object to an input mechanism of a wearable electronic device, the object being exterior to the wearable electronic device, the method comprising:

causing the input mechanism of the wearable electronic device to act as a first electrode of a proximity sensor, the input mechanism having an exterior contact surface that is electrically connected to the proximity sensor;

causing a housing of the wearable electronic device to act as a second electrode of the proximity sensor, wherein the housing is electrically connected to the proximity sensor and is electrically isolated from the input mechanism; and

measuring, by the proximity sensor, a change in a capacitance between the input mechanism and the housing;

wherein the input mechanism is operable to be moved in a direction toward the housing.

13. The method of claim 12 , further comprising altering output provided on a display of the wearable electronic device when the change in the capacitance exceeds a threshold.

14. The method of claim 12 , further comprising:

causing the input mechanism to remain in an active state when the change in the capacitance exceeds a threshold; and

causing the input mechanism to transition to an inactive state when the change in the electrical signal is below the threshold.

15. The method of claim 12 , wherein:

the input mechanism comprises a rotatable crown that is electrically connected to a shaft that extends through the housing; and

the user contact surface is on the rotatable crown.