WM8985
Pre-Production
REGISTER
ADDRESS
BIT
LABEL
DEFAULT
DESCRIPTION
R44 (2Ch)
0
LIP2INPPGA
1
Connect LIP pin to left channel input PGA
amplifier positive terminal.
Input
Control
0 = LIP not connected to input PGA
1 = input PGA amplifier positive terminal
connected to LIP (constant input
impedance)
1
2
LIN2INPPGA
L2_2INPPGA
1
0
Connect LIN pin to left channel input PGA
negative terminal.
0 = LIN not connected to input PGA
1 = LIN connected to input PGA amplifier
negative terminal.
Connect L2 pin to left channel input PGA
positive terminal.
0 = L2 not connected to input PGA
1 = L2 connected to input PGA amplifier
positive terminal (constant input
impedance).
4
RIP2INPPGA
1
Connect RIP pin to right channel input
PGA amplifier positive terminal.
0 = RIP not connected to input PGA
1 = right channel input PGA amplifier
positive terminal connected to RIP
(constant input impedance)
5
6
RIN2INPPGA
R2_2INPPGA
1
0
Connect RIN pin to right channel input
PGA negative terminal.
0 = RIN not connected to input PGA
1 = RIN connected to right channel input
PGA amplifier negative terminal.
Connect R2 pin to right channel input PGA
positive terminal.
0 = R2 not connected to input PGA
1 = R2 connected to input PGA amplifier
positive terminal (constant input
impedance).
Table 6 Input PGA Control
INPUT PGA VOLUME CONTROLS
The input microphone PGAs have a gain range from -12dB to +35.25dB in 0.75dB steps. The gain
from the LIN/RIN input to the PGA output and from the L2/R2 amplifier to the PGA output are always
common and controlled by the register bits INPPGAVOLL[5:0] and INPPGABVOLR[5:0]. These
register bits also affect the LIP pin when LIP2INPPGA=1, the L2 pin when L2_2INPPGA=1, the RIP
pin when RIP2INPPGA=1 and the L2 pin when L2_2INPPGA=1.
When the Automatic Level Control (ALC) is enabled the input PGA gains are controlled
automatically and the INPPGAVOLL and INPPGAVOLR bits should not be used.
PP, Rev 3.4, October 2006
30
w
WOLFSON [ WOLFSON MICROELECTRONICS PLC ]
