TFA9812_2
© NXP B.V. 2009. All rights reserved.
Preliminary data sheet
Rev. 02 — 22 January 2009
31 of 66
NXP Semiconductors
TFA9812
BTL stereo Class-D audio amplifier with I
2
S input
9.5.1 Interpolator settings and soft mute
9.5.2 Volume control
Table 28.
Register address 00h: miscellaneous I
2
C interpolator settings
Bit
15
14
13
12
11
10
9
8
Symbol
RSD
RSD
RSD
RSD
RSD
RSD
RSD
RSD
Default
0
0
0
0
0
0
0
0
Bit
7
6
5
4
3
2
1
0
Symbol
RSD
INV_POL
ROFF1
ROFF0
FDEMP2
FDEMP1
FDEMP0
S_MUTE
Default
0
0
1
0
0
0
0
1/0
Table 29.
Bit description of register 00h: miscellaneous I
2
C interpolator settings
Bit
Symbol
Description
6
INV_POL
Enable polarity inversion:
0 = No polarity inversion (left audio signal connected to
channel 1; right signal to channel 2)
1 = Polarity inversion enabled
5 to 4
ROFF[1:0]
Filter roll-off sharpness:
0 = Slow filter roll-off (2 to 8 f
s
)
≥
stop band > 0.7619 f
s
1 = Slow filter roll-off (2 to 8 f
s
)
≥
stop band > 0.7619 f
s
2 = Fast filter roll-off (2 to 8 f
s
)
≥
stop band > 0.6094 f
s
3 = Fast filter roll-off (2 to 8 f
s
)
≥
stop band > 0.6094 f
s
3 to 1
FDEMP[2:0]
Digital de-emphasis setting:
0 = No digital de-emphasis
1 = Digital de-emphasis for f
s
= 32 kHz
2 = Digital de-emphasis for f
s
= 44.1 kHz
3 = Digital de-emphasis for f
s
= 48 kHz
4 = Digital de-emphasis for f
s
= 96 kHz
5 to 8 = No digital de-emphasis
0
S_MUTE
Soft mute:
0 = Soft mute disabled using raised cosine (default in
Legacy control mode)
1 = Soft mute enabled using raised cosine (default in
I
2
C control mode)
Table 30.
Register address 01h: volume control
Bit
15
14
13
12
11
10
9
8
Symbol
VOL_L7
VOL_L6
VOL_L5
VOL_L4
VOL_L3
VOL_L2
VOL_L1
VOL_L0
Default
0
0
0
0
0
0
0
0
Bit
7
6
5
4
3
2
1
0
Symbol
VOL_R7
VOL_R6
VOL_R5
VOL_R4
VOL_R3
VOL_R2
VOL_R1
VOL_R0
Default
0
0
0
0
0
0
0
0
