92hdw74c Integrated Device Technology, 92hdw74c Datasheet - Page 19

• Manufacturer Part Number: 92hdw74c
• Description: 6-channel Hd Audio Codec, Single Or Dual Spdif
• Manufacturer: Integrated Device Technology

SIX CHANNEL HD AUDIO CODEC, PREMIUM WLP 3/4 COMPLIANT
92HDW74C1
SIX CHANNEL HD AUDIO CODEC, PREMIUM WLP 3/4 COMPLIANT
1.4.10. Low-voltage HDA Signaling
1.4.11.
the CODEC to become active, the driver will immediately transition the CODEC from D3 to D0. To
enable this use model, the CODEC must resume within 10mS and not pop.
The default power state for the Audio Function Group after reset is D3-default
1.4.9.5.
The programmable values, exposed via vendor-specific settings, are under the IDT Device Driver
control for further power reduction.
The 92HDW74C1 is compatible with either 1.5V or 3.3V HDA bus signaling; the voltage selection is
done dynamically based on the input voltage of DVDD_IO.
When in 1.5V mode, the 92HDW74C1 can correctly decode BITCLK, SYNC, RESET# and SDO as
they operate at 1.5V; additionally it will drive SDI and SDO at 1.5V. None of the GPIOs are affected,
as they always function at their nominal voltage (DVDD or AVDD).
Multi-channel capture
The capability to assign multiple ADC “Input Converters” to the same stream is supported to meet
the microphone array requirements of Vista and future operating systems. Single converter streams
are still supported and is done by assigning unique non zero Stream IDs to each converter. All cap-
ture devices (ADCs 0 and 1) may be used to create a multi-channel input stream. There are no
restrictions regarding digital microphones. However, the SPDIF input can not be used with an ADC
to create a 4-channel stream. SPDIF_In only supports stereo capture.
The ADC Converters can be associated with a single stream as long as the sample rate and the bits
per sample are the same. The assignment of converter to channel is done using the “CnvtrID” widget
and is restricted to even values. The ADC converters will always put out a stereo sample and there-
fore require 2 channels per converter.
The stream will not be generated unless all entries for the targeted converters are set identically, and
the total number of assigned converter channels matches the value in the NmbrChan field. These
are listed the “Multi-Converter Stream Critical Entries” table.
An example of a 4 Channel Steam with ADC0 supplying channels 0&1 and ADC1 supplying chan-
nels 2&3 is shown below. A 4 Channel stream can be created by assigning the same non-zero
stream id “Strm= N” to both ADC0 and ADC1. The sample rates must be set the same and the num-
ber of channels must be set to 4 channels “NmbrChan = 0011”.
ADC1 CnvtrID
ADC0 CnvtrID
AFG D3 and vendor specific verbs
Table 8: Example channel mapping
(NID = 0x08)
(NID = 0x07)
[3:0]
[3:0]
19
Ch = 2
Ch = 0
92HDW74C1
PC AUDIO
V 1.0 03/08