×

Audio and USB multiplexing

  • US 7,899,946 B2
  • Filed: 01/11/2008
  • Issued: 03/01/2011
  • Est. Priority Date: 01/11/2008
  • Status: Active Grant
First Claim
Patent Images

1. An analog/digital switching circuit for connecting a primary device to a peripheral device, the primary device comprising a primary USB connector, a power/audio manager and at least one primary listening device, and the peripheral device comprising a peripheral USB connector and at least one peripheral listening device comprising:

  • first and second data signal lines connected to the power/audio manager, for transmitting respective first and second data signals;

    first and second audio signal lines for transmitting respective first and second audio signals generated by the power/audio manager to the at least one primary listening device or the at least one peripheral listening device;

    first and second primary USB signal lines connected to the primary USB connector, for transmitting respective first and second USB signals;

    first and second peripheral USB signal lines connected to the peripheral USB connector and to the respective first and second primary USB signal lines;

    a USB detection line connected to the power/audio manager, to the primary USB connector and to the peripheral USB connector, for detecting a USB charger attached to the primary USB connector or to the peripheral USB connector;

    a first switch for multiplexing the first USB signal to the first data signal or the first audio signal;

    a second switch for multiplexing the second USB signal to the second data signal or the second audio signal; and

    configuration detection circuitry for detecting, based on states of said first and second switches, each of the following configurations;

    (c1) primary device not connected to peripheral device, audio not to be output to a primary listening device, USB charger not connected to primary device;

    (c2) primary device not connected to peripheral device, audio is to be output to a primary listening device, USB charger not connected to primary device;

    (c3) primary device not connected to peripheral device, audio not to be output to a primary listening device, USB charger is connected to primary device;

    (c4) primary device not connected to peripheral device, audio is to be output to a primary listening device, USB charger is connected to primary device;

    (c5) primary device is connected to peripheral device, audio not to be output to a peripheral listening device, USB charger not connected to peripheral device;

    (c6) primary device is connected to peripheral device, audio is to be output to a peripheral listening device, USB charger not connected to peripheral device;

    (c7) primary device is connected to peripheral device, audio not to be output to a peripheral listening device, USB charger is connected to peripheral device; and

    (c8) primary device is connected to peripheral device, audio is to be output to a peripheral listening device, USB charger is connected to peripheral device.

View all claims
  • 5 Assignments
Timeline View
Assignment View
    ×
    ×