VS1003 - MP3 / WMA / MIDI Audio Codec Circuit

Block diagram


VS1003 is a versatile slave MP3 and WMA decoder chip, replacing the discontinued VS1002. It can record wideband speech quality audio and play MIDI either from files or using a standard serial MIDI keyboard with the Real-Time MIDI Input Application. Many wide-ranging applications have been developed for this IC that has sold more than 5 million units.


  • Decodes MP3 (MPEG 1 & 2 audio layer III) (CBR +VBR +ABR);
    WMA 4.0/4.1/7/8/9 all profiles (5-384kbit/s);
    General MIDI / SP-MIDI files
  • Encodes IMA ADPCM from microphone or line input
  • Streaming support
  • Bass and treble controls
  • Operates with a single 12 - 13 MHz clock
  • Internal PLL clock multiplier
  • Low-power operation
  • High-quality on-chip stereo DAC with no phase error between channels
  • Stereo earphone driver capable of driving a 30­ ohm load
  • Separate operating voltages for analog, digital and I/O
  • 5.5 KiB On-chip RAM for user code / data
  • Serial control and data interfaces
  • Can be used as a slave co-processor
  • SPI flash boot for special applications
  • UART for debugging purposes
  • New functions may be added with software and 4 GPIO pins

Product variations

Device ID (order code) Package
VS1003B-L LQFP-48
VS1003B-B (not recommend for new designs) BGA-49


LQFP48 7x7x1.4mm
BGA49 7x7x1.4mm