wm9081 Wolfson Microelectronics plc, wm9081 Datasheet - Page 79

• Manufacturer Part Number: wm9081
• Description: Mono Dac With 2.6w Class Ab/d Speaker Driver, Dynamic Range Controller And Retune Mobile Parametric Equalizer
• Manufacturer: Wolfson Microelectronics plc

Pre-Production
POWER MANAGEMENT
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POWER MANAGEMENT REGISTERS
The WM9081 has many control registers that allow users to select which functions are active. For
minimum power consumption, unused functions should be disabled. To minimise pop or click noise,
it is important to enable or disable functions in the correct order. Note that, under the recommended
usage conditions of the WM9081, these features will be configured by running the default control
sequences as described in the “Control Write Sequencer” section. In these cases, many of these
register fields will be configured automatically.
R4 (04h)
VMID Control
R5 (05h)
Bias Control
1
R11 (0Bh)
Power
Management
R14 (0Eh)
Clock Control
3
REGISTER
ADDRESS
BIT
2:1
1
8
7
4
2
1
0
5
2
1
VMID_SEL [1:0]
BIAS_ENA
TSHUT_ENA
TSENSE_ENA
LINEOUT_ENA
SPKPGA_ENA
SPK_ENA
DAC_ENA
CLK_OP_ENA
CLK_TO_ENA
CLK_DSP_ENA
LABEL
DEFAULT
00
0
1
1
0
0
0
0
0
0
0
VMID Divider Enable and Select
00 = VMID disabled (for OFF mode)
01 = 2 x 40kΩ divider (for normal
operation)
10 = 2 x 240kΩ divider (for low power
standby)
11 = 2 x 5kΩ divider (for fast start-up)
Enables the Normal bias current
generator (for all analogue functions)
0 = Disabled
1 = Enabled
Thermal shutdown control
(Causes audio outputs to be disabled if
an over-temperature occurs. The thermal
sensor must also be enabled.)
0 = Disabled
1 = Enabled
Thermal sensor enable
0 = Disabled
1 = Enabled
LINEOUT Enable
0 = Disabled
1 = Enabled
Speaker PGA Enable
0 = Disabled
1 = Enabled
Speaker Output Enable
0 = Disabled
1 = Enabled
DAC Enable
0 = Disabled
1 = Enabled
Clock Output Enable
0 = Disabled
1 = Enabled
This bit enables OPCLK output on the
MCLK pin.
Frequency is set by CLK_OP_DIV.
TOCLK (timeout/ slow clock) Enable
0 = Disabled
1 = Enabled
CLK_DSP enable
0 = Disabled
1 = Enabled
DESCRIPTION
PP, Rev 3.0, April 2009
WM9081
79