WM8990ECS/RV Wolfson Microelectronics, WM8990ECS/RV Datasheet - Page 132

• Manufacturer Part Number: WM8990ECS/RV
• Description: Audio CODECs Stereo CODEC w.Class AB/D speaker driver
• Manufacturer: Wolfson Microelectronics

Specifications of WM8990ECS/RV

• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

WM8990
w
Table 79 Power Management
CHIP RESET AND ID
The device ID can be read back from register 0. Writing to this register will reset the device.
Table 80 Chip Reset and ID
SAVING POWER AT HIGHER SUPPLY VOLTAGE
The AVDD supply of the WM8990 can operate between 2.7V and 3.6V. By default, all analogue
circuitry on the device is optimized to run at 3.3V. This set-up is also good for all other supply
voltages down to 2.7V. At lower voltages, performance can be improved by increasing the bias
current. If low power operation is preferred the bias current can be left at the default setting. This is
controlled as shown in Table 81.
Table 81 Bias Optimisation
REGISTER
ADDRESS
R51 (33h)
R0 (00h)
Reset / ID
REGISTER
REGISTER
ADDRESS
ADDRESS
1
0
BIT
15:0
8:7
BIT
BIT
DACL_ENA
(rw)
DACR_ENA
(rw)
SW_RESET_C
HIP_ID
[15:0]
(rr)
LABEL
VSEL
[1:0]
LABEL
LABEL
11
DEFAULT
DEFAULT
0b
0b
8990h
DEFAULT
Analogue Bias Optimisation
00 = Reserved
01 = Bias current optimized for AVDD=2.7V
1X = Bias current optimized for AVDD=3.3V
Left DAC Enable
0 = disabled
1 = enabled
Right DAC Enable
0 = disabled
1 = enabled
Writing to this register resets all
registers to their default state.
Reading from this register will indicate
device family ID 8990h.
DESCRIPTION
DESCRIPTION
DESCRIPTION
PD, March 2009, Rev 4.0
Production Data
132