Data Sheet
PRELIMINARY
VS1063a Datasheet
8 SUPPORTED AUDIO FORMATS
clock. PS and SBR operation is automatically switched off if the internal clock is too slow for
correct decoding. Generally HE-AAC v2 files need 4.5× clock to decode both SBR and PS
content. This is why 3.5× + 1.0× clock is the recommended default.
For AAC the streaming ADTS format is recommended. This format allows easy rewind and fast
forward because resynchronization is easily possible.
In addition to ADTS (.aac), MPEG2 ADIF (.aac) and MPEG4 AUDIO (.mp4 / .m4a) files are
played, but these formats are less suitable for rewind and fast forward operations. You can still
implement these features by using the jump points table, or using slightly less robust but much
easier automatic resync mechanism (see Section 10.5.4).
Because 3GPP (.3gp) and 3GPPv2 (.3g2) files are just MPEG4 files, those that contain only
HE-AAC or HE-AACv2 content are played.
Important Note: To be able to play the .3gp, .3g2, .mp4 and .m4a files, the mdat atom must
be the last atom in the MP4 file. Because VS1063a receives all data as a stream, all metadata
must be available before the music data is received. Several MP4 file formatters do not satisfy
this requirement and some kind of conversion is required. This is also why the streamable
ADTS format is recommended.
Programs exist that optimize the .mp4 and .m4a into so-called streamable format that has the
mdat atom last in the file, and thus suitable for web servers’ audio streaming. You can use this
kind of tool to process files for VS1063a too. For example .
AAC
12
:
Samplerate / Hz Maximum Bitrate kbit/s - for 2 channels
≤96 132 144 192 264 288 384 529 576
48000 + + + + + + + + +
44100 + + + + + + + +
32000 + + + + + + +
24000 + + + + + +
22050 + + + + +
16000 + + + +
12000 + + +
11025 + +
8000 +
1
64000 Hz, 88200 Hz, and 96000 Hz AAC files are played at the highest possible samplerate
(48000 Hz with 12.288 MHz XTALI).
2
Also all variable bitrate (VBR) formats are supported. Note that the table gives the maximum
bitrate allowed for two channels for a specific samplerate as defined by the AAC specification.
The decoder does not actually have a fixed lower or upper limit.
Version: 0.42, 2011-11-24 28