Production Data
WM8945
REGISTER
ADDRESS
BIT
LABEL
DEFAULT
DESCRIPTION
REFER TO
Video buffer enable
0 = Disabled
R38 (26h)
Video Buffer
7
VB_ENA
0
1 = Enabled
Video buffer filter Q-Boost control
0 = Disabled
6
5
VB_QBOOST
VB_GAIN
0
0
1 = Enabled
Video buffer gain
0 = 0dB (=6dB unloaded)
1 = 6dB (=12dB unloaded)
Video buffer DC offset control
000 = Reserved
4:2
VB_DISOFF
[2:0]
111
001 = 40mV offset
010 = Reserved
011 = 20mV offset
100 = Reserved
101 = Reserved
110 = Reserved
111 = 0mV offset
Note – the specified offset applies to the 0dB gain
setting (VB_GAIN=0). When 6dB gain is selected, the
DC offset is doubled.
Video buffer pull-down
1
0
VB_PD
0
0
0 = pull-down disabled
1 = pull-down enabled
Enable the clamp between the video input and ground
0 = no clamp
VB_CLAMP
1 = Video buffer input is clamped to ground
Register 26h Video Buffer
REGISTER
ADDRESS
BIT
LABEL
DEFAULT
DESCRIPTION
REFER TO
AUX2 pin configuration
0 = Non-Audio signal
R39 (27h)
Input ctrl
8
AUX2_AUDIO
0
1 = AC-coupled Audio signal
AUX1 pin configuration
0 = Non-Audio signal
7
6
AUX1_AUDIO
MICB_LVL
0
0
1 = AC-coupled Audio signal
Microphone Bias Voltage control
0 = 0.9 x LDOVOUT
1 = 0.65 x LDOVOUT
Left Input PGA Inverting Input Select
0 = Connected to VMID
1 = Connected to IN2L
4
MICLN_TO_N_
PGAL
1
Left Input PGA Non-Inverting Input Select
00 = Connected to IN2L
01 = Connected to IN1L
10 = Connected to AUX1
11 = Reserved
1:0
P_PGAL_SEL
[1:0]
01
Register 27h Input ctrl
PD, May 2011, Rev 4.1
133
w
WOLFSON [ WOLFSON MICROELECTRONICS PLC ]
