WM8987L Datasheet, PDF (33/58 Pages) Wolfson Microelectronics plc – Stereo CODEC for Portable Audio Applications

Pre-Production
WM8987L
REGISTER
ADDRESS
R41 (29h)
ROUT2
Volume
BIT
LABEL
DEFAULT
6:0 ROUT2VOL 1111001
[6:0]
(0dB)
7
RO2ZC
0
8
RO2VU
0
R24 (18h)
4
ROUT2INV 0
Additional
Control (2)
Table 26 LOUT2/ROUT2 Volume Control
DESCRIPTION
ROUT2 volume
1111111 = +6dB
… (80 steps)
0110000 = -67dB
0101111 to 0000000 = Analogue MUTE
Left zero cross enable
1 = Change gain on zero cross only
0 = Change gain immediately
ROUT2 Volume Update
0 = Store ROUT2VOL in intermediate
latch (no gain change)
1 = Update gain for both channels
(right=ROUT2VOL, left=from
intermediate latch)
ROUT2 Invert
0 = No Inversion (0° phase shift)
1 = Signal inverted (180° phase shift)
For single-ended operation, the LO2VU and RO2VU bits provide a method to ensure that the left and
right channel gains are updated at the same time (irrespective of the time delay between writing to
registers R40 and R41).
OUT3 OUTPUT
The OUT3 pin can drive a 16Ω or 32Ω headphone or be used as a DC reference for a capless
headphone output (see page 55). OUT3SW selects the mode of operation required.
REGISTER
ADDRESS
R24 (18h)
Additional
Control (2)
BIT LABEL DEFAULT
8 OUT3SW
0
Table 27 OUT3 Select
DESCRIPTION
OUT3 select
0 : VREF
1 : mono mixer (volume controlled by MONOVOL)
When OUT3SW=1, OUT3 drives out the inverted signal from the mono mixer. In this case, the mono
mixer should be enabled (MONO=1 in R26). The signal amplitude at the OUT3 output can be
adjusted under software control by writing to MONOVOL in R42.
REGISTER
ADDRESS
R42 (2Ah)
Mono mixer
Volume
BIT
LABEL
6:0 MONOVOL
[6:0]
7
MOZC
Table 28 Mono Mixer Volume Control
DEFAULT
1111001
(0dB)
0
DESCRIPTION
Mono Mixer Volume
1111111 = +6dB
… (80 steps)
0110000 = -67dB
0101111 to 0000000 = Analogue MUTE
Mono Mixer zero cross enable
1 = Change gain on zero cross only
0 = Change gain immediately
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PP Rev 3.0 January 2007
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