WM8978 Wolfson Microelectronics Ltd., WM8978 Datasheet - Page 47

• Manufacturer Part Number: WM8978
• Description: The WM8978 is a low power, high quality stereo codec designed for portable applications such as Digital still camera or Digital Camcorde
• Manufacturer: Wolfson Microelectronics Ltd.

Preliminary Technical Data
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Table 25 DAC Digital Limiter Control
5-BAND GRAPHIC EQUALISER
Table 26 EQ and 3D Enhancement DAC or ADC Path Select
Table 27 EQ Band 1 Control
Table 28 EQ Band 2 Control
A 5-band graphic equaliser (EQ) is provided, which can be applied to the ADC or DAC path, together
with 3D enhancement, under control of the EQ3DMODE register bit.
The equaliser consists of low and high frequency shelving filters (Band 1 and 5) and three peak
filters for the centre bands. Each has adjustable cut-off or centre frequency, and selectable boost
(+/- 12dB in 1dB steps). The peak filters have selectable bandwidth.
R18
EQ Control 1
R18
EQ Band 1
Control
R19
EQ Band 2
Control
REGISTER
REGISTER
REGISTER
ADDRESS
ADDRESS
ADDRESS
6:4
8
4:0
6:5
4:0
6:5
8
BIT
BIT
BIT
LIMLVL
EQ3DMODE
EQ1G
EQ1C
EQ2G
EQ2C
EQ2BW
LABEL
LABEL
LABEL
000
1
01100
(0dB)
01
01100
(0dB)
01
0
DEFAULT
DEFAULT
DEFAULT
Programmable signal threshold level
(determines level at which the limiter
starts to operate)
000=-1dB
001=-2dB
010=-3dB
011=-4dB
100=-5dB
101 to 111=-6dB
0 = Equaliser and 3D Enhancement
applied to ADC path
1 = Equaliser and 3D Enhancement
applied to DAC path
Band 1 Gain Control. See Table 32 for
details.
Band 1 Cut-off Frequency:
00=80Hz
01=105Hz
10=135Hz
11=175Hz
Band 2 Gain Control. See Table 32 for
details.
Band 2 Centre Frequency:
00=230Hz
01=300Hz
10=385Hz
11=500Hz
Band 2 Bandwidth Control
0=narrow bandwidth
1=wide bandwidth
PTD Rev 2.6 November 2005
DESCRIPTION
DESCRIPTION
DESCRIPTION
WM8978
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