VLSI
Solution
y
VS1003b
VS1003
VS1003 - MP3/WMA AUDIO CODEC
Features
• Decodes MPEG 1 & 2 audio layer III (CBR
+VBR +ABR); WMA 4.0/4.1/7/8/9 all pro-
files (5-384kbit/s); WAV (PCM + IMA AD-
PCM); General MIDI / SP-MIDI files
• Encodes IMA ADPCM from microphone
or line input
• Streaming support for MP3 and WAV
• 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
30Ω load
• Separate operating voltages for analog, dig-
ital 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
Instruction
RAM
Instruction
ROM
Stereo
DAC
Mono
ADC
L
R
UART
Serial
Data/
Control
Interface
Stereo Ear−
phone Driver
DREQ
SO
SI
SCLK
XCS
RX
TX
audio
output
X ROM
X RAM
Y ROM
Y RAM
4
GPIO
GPIO
VSDSP
4
XDCS
VS1003
MIC AMP
Clock
multiplier
MUX
line
audio
mic
audio
Description
VS1003 is a single-chip MP3/WMA/MIDI audio
decoder and ADPCM encoder. It contains a high-
performance, proprietary low-power DSP proces-
sor core VS DSP
4
, working data memory, 5 KiB
instruction RAM and 0.5 KiB data RAM for user
applications, serial control and input data inter-
faces, 4 general purpose I/O pins, an UART, as
well as a high-quality variable-sample-rate mono
ADC and stereo DAC, followed by an earphone
amplifier and a common buffer.
VS1003 receives its input bitstream through a se-
rial input bus, which it listens to as a system slave.
The input stream is decoded and passed through a
digital volume control to an 18-bit oversampling,
multi-bit, sigma-delta DAC. The decoding is con-
trolled via a serial control bus. In addition to the
basic decoding, it is possible to add application
specific features, like DSP effects, to the user RAM
memory.
Version 1.04, 2009-02-03 1