Smart passive speaker drive
AssigneeNXP B.V.
InventorChristophe Macours
Life of this patent
Estimating the term…
Abstract
A circuit embodied in a mobile device is disclosed. The circuit includes a headphone audio driver, a loudspeaker audio driver and a switch coupled to outputs of the headphone audio driver and the loudspeaker audio driver. The switch is configured to connect the output of the loudspeaker audio driver to an external speaker when an external speaker is connected to the mobile device. The external speaker may be detected using methods such as automatic accessory detection or impedance measurement or a user configuration or a use action. The circuit may also include an impedance detector to drive the switch based on an impedance measurement. A user interface is provided to enable a user of the mobile device to driver the switch based on user preferences.
Claims20
A circuit embodied in a mobile device, comprising:
- a headphone audio driver;
- a loudspeaker audio driver;
- and
- a switch coupled to outputs of the headphone audio driver and the loudspeaker audio driver, wherein the switch is configured to connect, based on a user configuration stored in the mobile device, the output of the loudspeaker audio driver to an external speaker when the external speaker is connected to the mobile device, wherein the switch is configured to connect the output of the headphone audio driver to an external headphone when the external headphone is connected to the mobile device.
A method executable in a mobile device, the method comprising:
- measuring impedance of an external speaker connected to the mobile device;
- and
- based on a user configuration stored in the mobile device, connecting a loudspeaker amplifier of the mobile device to the external speaker via a switch when measured impedance is below a pre-selected threshold value and connecting a headphone audio amplifier to an external headphone via the switch when the measured impedance is above the pre-selected threshold value.
A mobile device, comprising:
- a headphone audio driver;
- a loudspeaker audio driver;
- a user interface to enable a user of the mobile device to drive the switch based on an user preference;
- and
- a switch coupled to outputs of the headphone audio driver and the loudspeaker audio driver, wherein based on the user preference, the switch is configured to connect the output of the loudspeaker audio driver to an external speaker when the external speaker is connected to the mobile device and the switch is configured to connect an output of the headphone audio driver to an external headphone when the external headphone is connected to the mobile device.
Dependencies are inferred from the claim text.