Audio control circuit
AssigneeAnpec Electronics Corporation
InventorChe-Chang Chang
Life of this patent
Estimating the term…
Abstract
An audio control circuit is provided in the present disclosure. The audio control circuit includes an input module, a volume signal detecting module and a volume adjusting module. The input module is used for receiving an audio signal. The volume signal detecting module is used for receiving a volume control signal and generates a volume adjusting signal according to the volume control signal. The volume adjusting module is used for receiving the audio signal and the volume adjusting signals and generates an amplified audio signal according to the audio signal and the volume adjusting signal. The volume control signal is a pulse width modulation signal.
Claims7
An audio control circuit, comprising:
- an input module configured to receive an audio signal;
- a volume control signal detecting module configured to receive an audio control signal, and including:
- a duty cycle calculating unit;
- a sampling unit configured to sample the audio control signal according to a clock signal, wherein a frequency value of the clock signal is greater than a frequency value of the audio control signal;
- a high level counting unit configured to calculate a high level signal time of each period of the audio control signal;
- and
- a low level counting unit configured to calculate a low level signal time of each period of the audio control signal, wherein the duty cycle calculating unit calculates a duty cycle percentage of each period of the audio control signal according to the high level signal time and the low level signal time, the volume control signal detecting module generating a volume adjusting signal according to the duty cycle percentage of each period of the audio control signal;
- and
- a volume adjusting module configured to receive the audio signal and the volume adjusting signal, and to generate an adjusted audio signal according to the audio signal and the volume adjusting signal;
- wherein the audio control signal is a pulse width modulation signal.
A volume adjusting method adopted for an audio control circuit, comprising:
- receiving an audio control signal and an audio signal;
- sampling the audio control signal according to a clock signal;
- calculating a high level signal time and a low level signal time of each period of the audio control signal, calculating a duty cycle percentage of each period of the audio control signal according to the high level signal time and the low level signal time, and providing a plurality of volume adjusting values corresponding to the duty cycle percentage of each period of the audio control signal;
- and
- adjusting a volume of the audio signal according to the volume adjusting values;
- wherein the audio control signal is a pulse width modulation signal.
Dependencies are inferred from the claim text.