WM8850
Pre-Production
STEREO LINE PLAYBACK
Stereo line playback is supported using the VOUT2LP, VOUT2LN, VOUT2RP and VOUT2RN pins;
these provide a differential stereo output through the DAC2 node. These outputs are intended for
line-level loads; the differential configuration provides noise rejection, particularly in the case of
lengthy signal tracks. An external differential to single-ended converter should be used for connection
to an external stereo jack. This path can provide two channels of a multi-channel playback system,
operating alongside the other two DAC paths.
Stereo line playback is also supported using the VOUT3LP, VOUT3LN, VOUT3RP and VOUT3RN
pins; these provide a differential stereo output through the DAC3 node. This path is identical in
function to the DAC2 path, so both paths are described together here. Note, however, that they are
completely independent paths and must be setup separately.
It is possible to configure either of the stereo line outputs to select the S/PDIF Rx node as the data
source. These signal paths are enabled using vendor-specific verbs, and are illustrated by the dotted
line in Figure 12.
The WM8850 nodes associated with this function are shown in Figure 12.
Figure 12 Stereo Differential Line Playback Paths
This section provides a summary of the DAC2, Port-G, DAC3 and Port-F nodes, and describes the
vendor-specific verb functions associated with each.
DAC2 (NID = 07h) AND DAC3 (NID = 08h)
Table 23 gives a summary of the DAC2 and DAC3 nodes:
NODE SUMMARY INFORMATION
NID
07h / 08h
Widget Type
Audio Converter
Supported Get Verbs
Supported Set Verbs
Unsolicited Responses
Vendor-Specific Verbs
Ah, Bh, F00h, F05h, F06h, F08h, F73h, F8Eh
2h, 3h, 705h, 706h, 708h, 773h, 78Eh
Stream Error
F73h, 773h : Internal Path Verb
F8Eh, 78Eh : Unsolicited Response Priority Control Verb
Table 23 DAC2 and DAC3 Nodes Summary Information
PP, April 2011, Rev 3.2
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