| 摘要 |
PURPOSE: A system chip including a voice CODEC and a stereo DAC is provided to integrate the voice CODEC and stereo DAC into one chip using a modulation technique to reduce a hardware size. CONSTITUTION: A system chip including a voice CODEC and a stereo DAC includes the first and second multiplexers, the first and second demultiplexers. The first multiplexer and the first demultiplexer selectively set a path to share a digital low pass filter according as a digital filter is used for the stereo DAC or voice CODEC. The second multiplexer and the second demultiplexer share an interpolator(21), a low pass filter(25), a digital SD modulator(28), and a digital/analog converter(29) in order to convert a digital audio signal for the stereo DAC and a digital audio signal for the voice CODEC into analog audio signals. The second multiplexer and demultiplexer selectively connect the output of the digital/analog converter to a corresponding analog low pass filter among the first and second analog low pass filters. |
