A low power MPEG-1/2 Layer I/II/III audio decoder with downsampling mode

This paper presents a low cost and low power MPEG-1/2 Lay I/II/III audio decoder. The decoder consists of a software core and a hardware core. By the corporation between the two parts, it can real-timely decode MPEG-1/2 Layer I/II/III audio bit-stream at a low clock frequency. A filtering architecture based on sub-band filter banks in perceptual audio coding is proposed. Using the new filtering architecture, the decoder can work at downsampling mode, which can decrease the power consumption of both the decoder and the output digital-to-analog converter. The proposed filter architecture also provides better signal-to-noise-ratio than before.