WM8976GEFL/V Wolfson Microelectronics, WM8976GEFL/V Datasheet - Page 29

• Manufacturer Part Number: WM8976GEFL/V
• Description: Audio CODECs Mono ADC Stereo DAC with Spkr
• Manufacturer: Wolfson Microelectronics

Specifications of WM8976GEFL/V

• Mounting Style: SMD/SMT
• Package / Case: QFN-32
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

Production Data
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Table 13 ADC Control
SELECTABLE HIGH PASS FILTER
Table 14 ADC Enable Control
Table 15 High Pass Filter Cut-off Frequencies (HPFAPP=1). Values in Hz.
The polarity of the output signal can also be changed under software control using the ADCLPOL
register bit.
With ADCOSR=0 the oversample rate is 64x which gives lowest power operation and when
ADCOSR=1 the oversample rate is 128x which gives best performance.
A selectable high pass filter is provided. To disable this filter set HPFEN=0. The filter has two
modes controlled by HPFAPP. In Audio Mode (HPFAPP=0) the filter is first order, with a cut-off
frequency of 3.7Hz. In Application Mode (HPFAPP=1) the filter is second order, with a cut-off
frequency selectable via the HPFCUT register. The cut-off frequencies when HPFAPP=1 are shown
in Table 15.
Note that the High Pass filter values (when HPFAPP=1) are calculated with the assumption that the
SR register bits are set correctly for the actual sample rate as shown in Table 15.
HPFCUT
[2:0]
000
001
010
011
100
101
110
111
R14
ADC Control
R14
ADC Control
REGISTER
ADDRESS
REGISTER
ADDRESS
The oversampling rate of the ADC can be adjusted using the ADCOSR register bit.
102
131
163
204
261
327
408
82
8
8
7
6:4
SR=101/100
BIT
0
3
BIT
11.025
113
141
180
225
281
360
450
563
ADCLPOL
ADCOSR
HPFEN
HPFAPP
HPFCUT
LABEL
LABEL
122
153
196
245
306
392
490
612
12
102
131
163
204
261
327
408
16
82
1
0
000
DEFAULT
SR=011/010
0
0
DEFAULT
fs (kHz)
22.05
113
141
180
225
281
360
450
563
High Pass Filter Enable
0=disabled
1=enabled
Select audio mode or application mode
0=Audio mode (1
1=Application mode (2
HPFCUT)
Application mode cut-off frequency
See Table 15 for details.
122
153
196
245
306
392
490
612
24
ADC polarity adjust:
0=normal
1=inverted
ADC oversample rate select:
0=64x (lower power)
1=128x (best performance)
102
131
163
204
261
327
408
32
82
DESCRIPTION
DESCRIPTION
SR=001/000
st
44.1
order, fc = ~3.7Hz)
113
141
180
225
281
360
450
563
PD Rev 4.4 July 2009
nd
order, fc =
122
153
196
245
306
392
490
612
48
WM8976
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