sta339bw STMicroelectronics, sta339bw Datasheet - Page 70

• Manufacturer Part Number: sta339bw
• Description: 2.1-channel High-efficiency Digital Audio System
• Manufacturer: STMicroelectronics

Register description
6.20
70/77
Table 83.
When SVUPE = 1 the fade-in rate is defined by the SVUP[4:0] bits according to the formula:
Table 84.
When SVDWE = 1 the fade-out rate is defined by the SVDW[4:0] bits according to the
formula:
DRC RMS filter coefficients (addr 0x39 - 0x3E)
Signal level detection in DRC algorithm is computed usign the following formula:
where x(t) represents the audio signal applied to the limiter, and y(t) the measured level.
0
1
0
1
R_C0[23]
R_C0[15]
R_C1[23]
R_C1[15]
R_C0[7]
R_C1[7]
D7
D7
D7
D7
D7
D7
Fade-in rate = 48 / (SVUP[4:0] + 1) dB/ms.
Fade-in rate = 48 / (SVDW[4:0] + 1) dB/ms.
y(t) = c0 * abs(x(t)) + c1 * y(t-1)
0
1
1
0
1
0
SVDWE
SVUPE
Soft volume (increasing) setup
Soft volume (decreasing) setup
R_C0[22]
R_C0[14]
R_C1[22]
R_C1[14]
R_C0[6]
R_C1[6]
D6
D6
D6
D6
D6
D6
0
1
1
1
1
0
R_C0[21]
R_C0[13]
R_C1[21]
R_C1[13]
R_C0[5]
R_C1[5]
When volume is increased, use the default rate
When volume is increased, use the rates defined by SVUP[4:0] .
When volume is decreased, use the default rate
When volume is decreased, use the rates defined by SVDW[4:0] .
D5
D5
D5
D5
D5
D5
0
1
1
1
0
1
Doc ID 15251 Rev 4
R_C0[20]
R_C0[12]
R_C1[20]
R_C1[12]
R_C0[4]
R_C1[4]
D4
D4
D4
D4
D4
D4
0
0
1
1
0
0
R_C0[19]
R_C0[11]
R_C1[19]
R_C1[11]
R_C0[3]
R_C1[3]
D3
D3
D3
D3
D3
D3
0
1
1
1
0
0
Mode
Mode
R_C0[18]
R_C0[10]
R_C1[18]
R_C1[10]
R_C0[2]
R_C1[2]
D2
D2
D2
D2
D2
D2
0
1
1
1
0
1
R_C0[17]
R_C1[17]
R_C0[9]
R_C0[1]
R_C1[9]
R_C1[1]
D1
D1
D1
D1
D1
D1
0
1
1
1
0
1
STA339BW
R_C0[16]
R_C1[16]
R_C0[8]
R_C0[0]
R_C1[8]
R_C1[0]
D0
D0
D0
D0
D0
D0
1
0
1
0
0
0