WM8961
Pre-Production
REGISTER
ADDRESS
BIT
LABEL
DEFAULT
DESCRIPTION
R40 (28h)
Left Speaker
Volume
6:0
SPKLVOL
[6:0]
0000000
(MUTE)
SPK_LP/SPK_LN Volume
1111111 = +6dB
… 1dB steps down to
0110000 = -73dB
0101111 to 0000000 = Analogue MUTE
7
8
SPKLZC
SPKVU
0
0
Left Speaker Zero Cross Enable
1 = Change gain on zero cross only
0 = Change gain immediately
Speaker Volume Update
0 = Store SPKLVOL in intermediate
latch (no gain change)
1 = Update left and right channel gains
(left = SPKLVOL, right = intermediate
latch)
R41 (29h)
Right Speaker
Volume
6:0
SPKRVOL
[6:0]
0000000
(MUTE)
SPK_RP/SPK_RN Volume
1111111 = +6dB
… 1dB steps down to
0110000 = -73dB
0101111 to 0000000 = Analogue MUTE
7
8
SPKRZC
SPKVU
0
0
Right Speaker Zero Cross Enable
1 = Change gain on zero cross only
0 = Change gain immediately
Speaker Volume Update
0 = Store SPKRVOL in intermediate
latch (no gain change)
1 = Update left and right channel gains
(left = intermediate latch, right =
SPKRVOL)
R26 (1Ah)
Pwr Mgmt (2)
4
3
SPKL_PGA
SPKR_PGA
0
0
SPK_LP and SPK_LN left speaker PGA
Enable
SPK_RP and SPK_RN right speaker
PGA Enable
Table 34 SPK_L/SPK_R Analogue Volume Control
SPEAKER OUTPUT BOOST CONTROL
The speaker output boost stage allows AVDD to be run at a lower voltage to save power, while
maximum output power can be delivered to the load, maximising the full range of SPKVDD1 and
SPKVDD2 supplies. It is controlled by CLASSD_ACGAIN[2:0].
REGISTER
ADDRESS
BIT
LABEL
DEFAULT
DESCRIPTION
2:0
CLASSD_A
CGAIN
[2:0]
011
(1.68x)
AC Speaker Boost (Boosts speaker AC
output signal by up to 3.98 x on left and
right channels)
R51 (33h)
Class D
Control 2
000 = 1.00x boost (+0dB)
001 = 1.19x boost (+1.5dB)
010 = 1.41x boost (+3.0dB)
011 = 1.68x boost (+4.5dB)
100 = 2.00x boost (+6.0dB)
101 = 2.37x boost (+7.5dB)
110 = 2.81x boost (+9.0dB)
111 = 3.98x boost (+12dB)
Note that +12dB setting will cause a full
scale output signal to clip.
Table 35 SPK_L/SPK_R Speaker Boost Control
PP, August 2009, Rev 3.1
w
49
WOLFSON [ WOLFSON MICROELECTRONICS PLC ]
