VS1103B Datasheet, PDF (32/61 Pages) List of Unclassifed Manufacturers – MIDI/ADPCM AUDIO CODEC

VLSI
Solution ^y
VS1103b
VS1103B
6. FUNCTIONAL DESCRIPTION
of the users earphones without causing clipping.
VSBE is activated when SB AMPLITUDE is non-zero. SB AMPLITUDE should be set to the user’s
preferences, and SB FREQLIMIT to roughly 1.5 times the lowest frequency the user’s audio system can
reproduce. For example setting SCI BASS to 0x00a6 will give 15 dB enhancement below 60 Hz.
Note: Because VSBE tries to avoid clipping, it gives the best bass boost with dynamical music material,
or when the playback volume is not set to maximum. It also does not create bass from nothing: the
source material must have some bass to begin with.
Treble Control VSTC is activated when ST AMPLITUDE is non-zero. For example setting SCI BASS
to 0x7a00 will give 10.5 dB treble enhancement above 10 kHz.
Bass Enhancer uses about 3.0 MIPS and Treble Control 1.2 MIPS at 44100 Hz sample rate. Both can be
on simultaneously.
6.6.4 SCI CLOCKF (RW)
SCI CLOCKF is used to control the internal clock of VS1103b.
SCI CLOCKF bits
Name
Bits Description
SC MULT 15:13 Clock multiplier
SC ZERO 12:11 Set to zero
SC FREQ 10: 0 Clock frequency
SC MULT activates the built-in clock multiplier. This will multiply XTALI to create a higher CLKI.
The values are as follows:
SC MULT
0
1
2
3
4
5
6
7
MASK
0x0000
0x2000
0x4000
0x6000
0x8000
0xa000
0xc000
0xe000
CLKI
XTALI
XTALI×1.5
XTALI×2.0
XTALI×2.5
XTALI×3.0
XTALI×3.5
XTALI×4.0
XTALI×4.5
SC FREQ is used to tell if the input clock XTALI is running at something else than 12.288 MHz. XTALI
is set
in
4
kHz steps.
The
formula
for
calculating
the
correct value
for this
register is
XT ALI−8000000
4000
(XTALI is in Hz).
Note: As opposed to some other VS10XX chips, a software reset must be performed after SCI CLOCKF
has been set. It is recommended that SCI CLOCKF is set only after each hardware reset / startup.
Note: The default value 0 is assumed to mean XTALI=12.288 MHz.
Version 1.01, 2007-09-03
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