Patent ID: 8848932
Filing Date: 2014-09-30
Classification: H03G,H04R

Abstract:
1. An audio subsystem for a mobile device comprising at least one speaker, the audio subsystem comprising: an audio source for generating an audio signal; a proximity sensor comprising a detection circuit configured to generate a sensor output signal representing a distance to a user of the mobile device, and a failsafe generator coupled to the detection circuit and configured to generate a sensor status signal indicating an operational status of the proximity sensor; and a power amplification module configured to process the audio signal received from the audio source into an amplified audio signal for output by the at least one speaker, the power amplification module comprising a gain controller responsive to the sensor output signal and the sensor status signal to determine and apply a gain factor to the audio signal based on the distance to the user of the mobile device and the operational status of the proximity sensor; wherein the failsafe generator is configured to