wm8941 Wolfson Microelectronics plc, wm8941 Datasheet - Page 53

• Manufacturer Part Number: wm8941
• Description: Mono Codec With Speaker Driver And Video Buffer
• Manufacturer: Wolfson Microelectronics plc

Production Data
w
Figure 26 WM8941 Video Buffer Filter Response
-10
-15
-20
-25
10
-5
5
0
10
VIDEO BUFFER REGISTERS
Table 43 Video Buffer Registers
Video buffer enable / disable and gain are controlled via the following registers:
R3
Power management 3
R40
Video Buffer
REGISTER
ADDRESS
100
WM8941 Video Buffer Filter Response
-20dBV sinewave input, 0dB gain setting, VBVDD=3.3V
4
4
3
2
1
0
BIT
VBUFEN
QBOOST
VBGAIN
VBDISOFF
VBPULLDWN
VBCLAMPEN
Frequency (kHz)
LABEL
1000
0
0
0
0
0
0
DEFAULT
Video buffer enable
0 = disabled
1 = enabled
Increases the filters Q.
Video buffer gain
0 = 0dB (=6dB unloaded)
1 = +6dB (=12dB unloaded)
Disable Video Buffer DC Offset
0 = Video buffer drives down to
40mV above ground
1 = Video buffer drives to
ground (not recommended)
Video Buffer Pull-down
0=Normal
1=Enables high impedance
pull-down on in put to Video
buffer
Video buffer clamp enable
0 = disabled
1 = enabled
10000
PD, Rev 4.0, August 2008
DESCRIPTION
WM8941
0dB
0dB Qboost
6dB
6dB Qboost
100000
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