wm8976gefl-v Wolfson Microelectronics plc, wm8976gefl-v Datasheet - Page 80

• Manufacturer Part Number: wm8976gefl-v
• Description: Stereo Codec With Speaker Driver
• Manufacturer: Wolfson Microelectronics plc

WM8976
RECOMMENDED POWER UP/DOWN SEQUENCE
w
In order to
powered up and down using one of the following sequences:
Power-up when NOT using the output 1.5x boost stage:
1.
2.
3.
4.
5.
6.
7.
8.
9.
Power-up when using the output 1.5x boost stage:
1.
2.
3.
4.
5.
6.
7.
8.
9.
10. Enable other mixers as required.
11. Enable other outputs as required.
12. Set remaining registers.
Power Down (all cases):
1.
2.
3.
4.
5.
Turn on external power supplies. Wait for supply voltage to settle.
Mute all analogue outputs.
Set L/RMIXEN = 1 and DACENL/R = 1 in register R3.
Set BUFIOEN = 1 and VMIDSEL[1:0] to required value in register R1. Wait for the VMID supply
to settle. *Refer notes 1 and 2.
Set BIASEN = 1 in register R1.
Set L/ROUT1EN = 1 in register R2.
Enable other mixers as required.
Enable other outputs as required.
Set remaining registers.
Turn on external power supplies. Wait for supply voltage to settle.
Mute all analogue outputs.
Enable unused output chosen from L/ROUT2, OUT3 or OUT4. If unused output not available,
chose one of these outputs not required at power up.
Set BUFDCOPEN = 1 and BUFIOEN = 1 in register R1.
Set SPKBOOST = 1 in register R49.
Set VMIDSEL[1:0] to required value in register R1. Wait for the VMID supply to settle. *Refer
notes 1 and 2.
Set L/RMIXEN = 1 and DACENL/R = 1 in register R3.
Set BIASEN = 1 in register R1.
Set L/ROUT2EN = 1 in register R3. *Note 3.
Mute all analogue outputs.
Disable Power Management Register 1. R1 = 0x00.
Disable Power Management Register 2. R2 = 0x00.
Disable Power Management Register 3. R3 = 0x00.
Remove external power supplies.
escry e output pop and click noise, it is recommended that the WM8976 device is
PD Rev 4.4 July 2009
Production Data
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