WM8951L_07 WOLFSON [Wolfson Microelectronics plc], WM8951L_07 Datasheet - Page 15

• Manufacturer Part Number: WM8951L_07
• Description: Stereo ADC with Microphone Input and Clock Generator
• Manufacturer: WOLFSON [Wolfson Microelectronics plc]

Production Data
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Figure 9 Line Input Schematic
The gain between the line inputs and the ADC is logarithmically adjustable from +12dB to –34.5dB in
1.5dB steps under software control. The ADC Full Scale input is 1.0V rms at AVDD1/2 = 3.3 volts.
Any voltage greater than full scale will overload the ADC and cause distortion. Note that the full scale
input tracks directly with AVDD. The gain is independently adjustable on both Right and Left Line
Inputs. However, by setting the INBOTH bit whilst programming the volume control, both channels
are simultaneously updated with the same value. Use of INBOTH reduces the required number of
software writes required. The line inputs to the ADC can be muted in the analogue domain under
software control. The software control registers are shown Table 2. Note that the Line Input Mute
only mutes the input to the ADC, this will still allow the Line Input signal to pass to the line output in
Bypass Mode.
Table 2 Line Input Software Control
0000000
Left Line In
0000001
Right Line In
REGISTER
ADDRESS
LINEIN
4:0
7
8
4:0
7
8
BIT
12.5k
LINVOL[4:0]
LINMUTE
LRINBOTH
RINVOL[4:0]
RINMUTE
RLINBOTH
LABEL
VMID
10111
( 0dB )
1
0
10111
( 0dB )
1
0
DEFAULT
Left Channel Line Input Volume
Control
11111 = +12dB . . 1.5dB steps down
to 00000 = -34.5dB
Left Channel Line Input Mute to ADC
1 = Enable Mute
0 = Disable Mute
Left to Right Channel Line Input
Volume and Mute Data Load Control
1 = Enable Simultaneous Load of
LINVOL[4:0] and LINMUTE to
RINVOL[4:0] and RINMUTE
0 = Disable Simultaneous Load
Right Channel Line Input Volume
Control
11111 = +12dB . .1.5dB steps down
to 00000 = -34.5dB
Right Channel Line Input Mute to
ADC
1 = Enable Mute
0 = Disable Mute
Right to Left Channel Line Input
Volume and Mute Data Load Control
1 = Enable Simultaneous Load of
RINVOL[4:0] and RINMUTE to
LINVOL[4:0] and LINMUTE
0 = Disable Simultaneous Load
DESCRIPTION
PD Rev 4.1 December 2007
ADC
To
WM8951
15