The VS1011 is VLSI Solution's basic MP3 decoder chip. It has a reliable and high-quality MP3 and WAV decoding engine combined with a stereo D/A converter and earphone amplifier. Although intended as a slave processor, the VS1011 also has a standalone mode that can be used to create a simple standalone MP3 player.

• Decodes MP3 (MPEG 1.0 & 2.0 audio layer III (CBR, VBR, ABR));
  MP1 & MP2 (MPEG 1.0 & 2.0 audio layers I & II) optional; 
  WAV (PCM + IMA ADPCM)
• Full 320 kbit/s MP3 with 12.0 MHz external clock
• Streaming support for MP1/2/3 and WAV
• Bass and treble controls
• Operates with single 12 - 13 MHz or 24 - 26 MHz external clock
• Internal clock doubler
• Low-power operation
• High-quality stereo DAC with no phase error between channels
• Stereo earphone driver capable of driving a 30­ ohm load
• Separate 2.5...3.6 V operating voltages for analog and digital
• Serial control and data interfaces
• Can be used as a slave co-processor
• 5.5 KiB On-chip RAM for user code/data
• SPI flash boot for special applications
• New functions may be added with software and 4 GPIO pins