Abstract: Some embodiments of the disclosure provide systems and methods of detecting headphone orientation. The systems and methods described herein may be used, for example, to determine which ear cup of a pair of headphones is positioned on which ear of a user. By making this determination, stereophonic audio signals may be divided into their left audio channel signal and right audio channel signal components and transmitted to the proper ear cup. In another example, the systems and methods described herein may be used to determine when a pair of headphones are being worn on a user's head and/or are removed from a user's head. By determining when the headphones are being worn, the headphones may be able to automatically pause an audio signal and/or power off when a transition from on-head to off-head is detected.

Abstract: An electronic device such as an earphone may have sensor circuitry. The sensor circuitry may include optical proximity sensors and capacitive sensor circuitry. An ear support structure such as an ear hook may be used to hold the earphone adjacent to an ear of a user. In this position, a speaker in the earphone may be used to present audio to the user. The ear hook may be formed from an insulating elastomeric polymer. A stainless steel wire or other bendable structural support member may be embedded within the elastomeric polymer. The bendable member may hold the ear hook in a desired bent shape after bending by the user. The capacitive sensor circuitry may include one or more capacitive sensor electrodes coupled to capacitance-to-digital converter circuitry. Control circuitry may activate the optical proximity sensors in response to detection of a capacitance to confirm that the earphone is being worn.

Abstract: An earbud may include capacitive sensor electrodes and a capacitance-to-digital converter that is configured to make capacitance measurements with the capacitive sensor electrodes. The earbud may have a housing in which a speaker is mounted. A tubular portion of the housing may have a passageway that is aligned with the speaker. The tubular portion may be received within the ear canal of a user. The tubular portion may include a tubular member on which the capacitive sensor electrodes are formed. The tubular member may be formed from a compressible tubular member that is compressed when the earbud is worn in the ear of the user. Ring-shaped electrodes and other electrodes may be formed on the compressible tubular member. Control circuitry in the earbud may determine whether the earbud is fully or partially within the ear of a user based on the capacitance measurements.

Abstract: A data storage system is disclosed that utilizes a high performance caching architecture. In one embodiment, the caching architecture utilizes a cache table, such as a lookup table, for referencing or storing host data units that are cached or are candidates for being cached in the solid-state memory. Further, the caching architecture maintains a segment control list that specifies associations between particular cache table entries and particular data segments. Such separation of activities related to the implementation of a caching policy from activities related to storing cached data and candidate data provides robustness and scalability while improving performance.