WM8978_06 Datasheet, PDF (70/119 Pages) Wolfson Microelectronics plc – Stereo CODEC With Speaker Driver

WM8978
Pre-Production
Figure 35 Outputs OUT3 and OUT4
REGISTER BIT
ADDRESS
LABEL
R49
3
OUT3BOOST
Output control
DEFAULT
0
4
OUT4BOOST
0
R1
8
BUFDCOPEN
0
Power
management
1
Table 49 OUT3 and OUT4 Boost Stages Control
DESCRIPTION
0 = OUT3 output gain = -1;
DC = AVDD / 2
1 = OUT3 output gain = +1.5
DC = 1.5 x AVDD / 2
0 = OUT4 output gain = -1;
DC = AVDD / 2
1 = OUT4 output gain = +1.5
DC = 1.5 x AVDD / 2
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)
OUT3BOOST/
OUTPUT
OUT4BOOST ^{STAGE GAIN}
OUTPUT DC
LEVEL
0
1x
AVDD/2
1
1.5x
1.5xAVDD/2
Table 50 OUT3/OUT4 Output Boost Stage Details
OUTPUT STAGE
CONFIGURATION
Inverting
Non-inverting
w
PP Rev 3.0 May 2006
70