Production Data
WM8978
w
PD, Rev 4.5, October 2011
65
Figure 33 Outputs OUT3 and OUT4
REGISTER
ADDRESS
BIT LABEL DEFAULT
DESCRIPTION
R49
Output control
3
OUT3BOOST
0
0 = OUT3 output gain = -1;
DC = AVDD / 2
1 = OUT3 output gain = +1.5
DC = 1.5 x AVDD / 2
4
OUT4BOOST
0
0 = OUT4 output gain = -1;
DC = AVDD / 2
1 = OUT4 output gain = +1.5
DC = 1.5 x AVDD / 2
R1
Power
management
1
8
BUFDCOPEN
0
Dedicated buffer for DC level shifting
output stages when in 1.5x gain
boost configuration.
0=Buffer disabled
1=Buffer enabled (required for 1.5x
gain boost)
Table 46 OUT3 and OUT4 Boost Stages Control
OUT3BOOST/
OUT4BOOST
OUTPUT
STAGE GAIN
OUTPUT DC
LEVEL
OUTPUT STAGE
CONFIGURATION
0 1x
AVDD/2
Inverting
1 1.5x
1.5xAVDD/2
Non-inverting
Table 47 OUT3/OUT4 Output Boost Stage Details
Summary of Contents for WM8978
Page 11: ...Production Data WM8978 w PD Rev 4 5 October 2011 11 SPEAKER OUTPUT THD VERSUS POWER...
Page 14: ...WM8978 Production Data w PD Rev 4 5 October 2011 14 AUDIO PATHS OVERVIEW...
Page 55: ...Production Data WM8978 w PD Rev 4 5 October 2011 55 Figure 26 Left Right Output Channel Mixers...
Page 60: ...WM8978 Production Data w PD Rev 4 5 October 2011 60 Figure 29 Speaker Outputs LOUT2 and ROUT2...