WM8750L
Production Data
GRAPHIC EQUALISER
The WM8750L has a digital graphic equaliser and adaptive bass boost function. This function
operates on digital audio data before it is passed to the audio DACs. Bass enhancement can take two
different forms:
Linear bass control: bass signals are amplified or attenuated by a user programmable gain.
This is independent of signal volume, and very high bass gains on loud signals may lead to
signal clipping.
Adaptive bass boost: The bass volume is amplified by a variable gain. When the bass
volume is low, it is boosted more than when the bass volume is high. This method is
recommended because it prevents clipping, and usually sounds more pleasant to the
human ear.
Treble control applies a user programmable gain, without any adaptive boost function. Bass and
treble control are completely independent with separately programmable gains and filter
characteristics.
REGISTER
ADDRESS
BIT
LABEL
BB
DEFAULT
DESCRIPTION
R12 (0Ch)
Bass Boost
7
0
Bass Control
0 = Linear bass control
1 = Adaptive bass boost
BC
Bass Filter Characteristic
6
0
0 = Low Cutoff (130Hz at 48kHz sampling)
1 = High Cutoff (200Hz at 48kHz sampling)
Bass Intensity
BASS
[3:0]
3:0
1111
(Disabled)
Code
0000
0001
0010
0011
0100
0101
0110
0111
1000
1001
1010
1011
1100
1101
1110
1111
BB=0
+9dB
BB=1
15 (max)
+9dB
14
13
12
11
10
9
+7.5dB
+6dB
+4.5dB
+3dB
+1.5dB
0dB
8
-1.5dB
-3dB
7
6
-4.5dB
-6dB
5
4
-6dB
3
-6dB
2
-6dB
1
Bypass (OFF)
R13 (0Dh)
TC
Treble Filter Characteristic
6
0
Treble Control
0 = High Cutoff (8kHz at 48kHz sampling)
1 = Low Cutoff (4kHz at 48kHz sampling)
Treble Intensity
TRBL
[3:0]
3:0
1111
(Disabled)
0000 or 0001 = +9dB
0010 = +7.5dB
… (1.5dB steps)
1011 to 1110 = -6dB
1111 = Disable
Table 18 Graphic Equaliser
PD, Rev 4.4, August 2012
30
w
WOLFSON [ WOLFSON MICROELECTRONICS PLC ]
