MAS3587F datasheet(41/82 Pages) MICRONAS

41 / 82 page

ADVANCE INFORMATION

MAS 3587F

Micronas

3.3.5. DSP Volume Control

The digital baseband volume matrix is used for control-

ling the digital gain of the decoder as shown in Fig. 3–

3. This volume control is effective on both, the digital

audio output and the data stream to the D/A convert-

ers. The values are in 20-bit 2’s complement notation.

Table 3–9 shows the proposed settings for the 4 vol-

ume matrix coefficients for stereo, left and right mono.

The gain factors are given in fixed point notation

(

−1.0×219 = 80000

hex).

The DSP volume control is available in Decoder Mode

only.

Fig. 3–3: Digital volume matrix

If channels are mixed, care must be taken to prevent

clipping at high amplitudes. Therefore the sum of the

absolute values of coefficients for one output channel

should be less than 1.0.

For normal operating conditions it is recommended to

use the main volume control of the audio codec

instead (register 00 10hex of the audio codec).

−1

left audio

right audio

Table 3–9: Settings for the digital volume matrix

Memory

D0:354

D0:355

D0:356

D0:357

Name

Stereo

(default)

−1.0

Mono left

−1.0

Mono right

−1.0

Table 3–10: Content of D0:fd5 after reception of 19 ancillary bits.

D0:fd5

MSB

LSB

Ancillary

Data

4th

bit

5th

bit

6th

bit

...

17th

bit

18th

bit

last

bit

Table 3–11: Content of D0:fd6 after reception of 19 ancillary bits.

D0:fd6

MSB

LSB

Ancillary

Data

xxxx

xxxfirst

bit

2nd

bit

3rd

bit

MAS3587F Arkusz danych(PDF) 41 Page - Micronas

MAS3587F Arkusz danych(HTML) 41 Page - Micronas

Html Pages

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82

Arkusz danych Pobierz

Link URL