alc268 Realtek Semiconductor Corporation, alc268 Datasheet - Page 32

• Manufacturer Part Number: alc268
• Description: 2+2 Channel High Definition Audio Codec
• Manufacturer: Realtek Semiconductor Corporation

7.5. Power Management
The ALC268 does not support Wake-Up events when in low power mode. All power management state
changes in widgets are driven by software. Table 14 shows the System Power State Definitions.
In the ALC268, all the widgets include output/input converters support power control. Software may have
various power states depending on system configuration.
Table 15 indicates those nodes that support power management. To simplify power control, software can
configure whole codec power states through the audio function (NID=01h). Output converters (DACs)
and input converters (ADCs) have no individual power control to supply fine-grained power control.
2+2 Channel High Definition Audio Codec
Note: PD=Powered Down
Condition
LINK Response powered down
DAC powered down
ADC powered down
Headphone Driver powered down All headphone drivers are powered down.
Mixers powered down
Reference power down
Audio Function
Power States
(NID=01h)
D3 (Cold)
D3 (Hot)
D0
D1
D2
Definitions
All power on. Individual DACs and ADCs can be powered up or down as required.
All amplifiers and converters (DACs and ADCs) are powered down. State maintained, analog
reference stays up.
All amplifiers and converters (DACs and ADCs) are powered down. State maintained, but analog
reference off (D1 + analog reference off).
Power still supplied. The codec stops the internal clock. State is maintained.
All power removed. State lost.
Description
LINK Response
DACs
ADCs
All Headphone Drivers
All Mixers
All Reference
Table 14. System Power State Definitions
Description
Internal clock is stopped. SDATA-IN and S/PDIF-OUT are floated with pulled low
47K resistors internally. Detection of ‘Link Reset Entry’ and ‘Link Reset Exit’
sequences are supported. All states are maintained if DVDD is supplied.
Analog block and digital filter are powered down.
Analog block and digital filter are powered down. The data on SDATA-IN is quiet.
All internal mixer widgets are powered down. The DC reference and VREFOUTx at
individual pin complex are still alive.
All internal references, DC reference, and VREFOUTx at individual pin complexes
are off.
Table 15. Power Controls in NID=01h
Table 16. Powered Down Conditions
Normal
Normal
Normal
Normal
Normal
Normal
D0
24
Normal
Normal
Normal
Normal
PD
PD
D1
Normal
PD
PD
PD
PD
PD
D2
Track ID: JATR-1076-21
D3 (Hot/Cold)
PD
PD
PD
PD
PD
PD
ALC268 Series
Link Reset
Datasheet
Normal
Normal
Normal
PD
PD
PD
Rev. 1.3