SGTL5000_13 Datasheet, PDF (56/68 Pages) Freescale Semiconductor, Inc – Low Power Stereo Codec with Headphone Amp

FUNCTIONAL DEVICE OPERATION
PROGRAMMING EXAMPLES
Table 58. DAP_AVC_ATTACK 0x0128
15
14
13
12
11
10
9
8
7
6
5
4
3
2
1
0
RSVD
RATE
BITS
15:12
11:0
FIELD
RSVD
RATE
RW RESET
DEFINITION
RO
0x0
Reserved
RW
0x28
AVC Attack Rate
This is the rate at which the AVC applies attenuation to the signal to bring it to the
threshold level. AVC Attack Rate is programmable. To use a custom rate, use the
formula below to convert from dB/S to hex value:
Hex Value = (1 - (10^(-(Rate_dBs/(20*SYS_FS)))) * 2^19
where, SYS_FS is the system sample rate configured in CHIP_CLK_CTRL register.
Example values:
0x28 = 32 dB/s
0x10 = 8.0 dB/s
0x05 = 4.0 dB/s
0x03 = 2.0 dB/s
Table 59. DAP_AVC_DECAY 0x012A
15
14
13
12
11
10
9
8
7
6
5
4
3
2
1
0
RSVD
RATE
BITS
15:12
11:0
FIELD
RSVD
RATE
RW RESET
DEFINITION
RO
0x0
Reserved
RW
0x50
AVC Decay Rate
This is the rate at which the AVC releases the attenuation previously applied to the
signal during attack. AVC Decay Rate is programmable. To use a custom rate, use the
formula below to convert from dB/S to hex value:
Hex Value = (1 - (10^(-(Rate_dBs/(20*SYS_FS)))) * 2^23
where, SYS_FS is the system sample rate configured in CHIP_CLK_CTRL register.
Example values:
0x284 = 32 dB/s
0xA0 = 8.0 dB/s
0x50 = 4.0 dB/s
0x28 = 2.0 dB/s
Table 60. DAP_COEF_WR_B1_MSB 0x012C
15 14 13 12 11 10
9
8
7
6
5
4
3
2
1
0
MSB
BITS
15:0
FIELD
MSB
RW RESET
DEFINITION
RW
0x0
Most significant 16-bits of the 20-bit filter coefficient that needs to be written
SGTL5000
56
Analog Integrated Circuit Device Data
Freescale Semiconductor