WM8912 datasheet(31/129 Pages) CIRRUS

31 / 129 page

Production Data

WM8912

PD, Rev 4.1, February 2013

DIGITAL MIXING

The digital DAC data can be controlled in various ways to support a range of different usage modes.

Data from either of the digital audio interface channels can be routed to either the left or the right

DAC. The DACs can be configured as a mono mix of the two audio channels. See "Digital Audio

Interface Control" for more information on the audio interface.

The WM8912 provides a Dynamic Range Control (DRC) feature, which can apply compression and

gain adjustment in the digital domain to the DAC signal path. This is effective in controlling signal

levels under conditions where input amplitude is unknown or varies over a wide range. See “Dynamic

Range Control (DRC)” for further details.

The W8912 also incorporates the ReTune

Mobile 5-band parametric equaliser with fully

programmable coefficients for optimization of speaker characteristics or for tailoring the response

according to user preferences. See “ReTune

TM Mobile Parametric Equalizer (EQ)” for further details.

DAC INTERFACE ROUTING AND CONTROL

The input data source for each DAC can be changed under software control using register bits

AIFDACL_SRC and AIFDACR_SRC. The polarity of each DAC input may also be modified using

ADDRESS

BIT

LABEL

DEFAULT

DESCRIPTION

R24 (18h)

Audio

Interface 0

DACL_DATINV

Left DAC Invert

0 = Left DAC output not inverted

1 = Left DAC output inverted

DACR_DATINV

Right DAC Invert

0 = Right DAC output not inverted

1 = Right DAC output inverted

AIFDACL_SRC

Left DAC Data Source Select

0 = Left DAC outputs left interface data

1 = Left DAC outputs right interface data

AIFDACR_SRC

Right DAC Data Source Select

0 = Right DAC outputs left interface data

1 = Right DAC outputs right interface

data

Table 13 DAC Routing and Control

DAC INTERFACE VOLUME BOOST

A digital gain function is available at the audio interface to boost the DAC volume when a small signal

is received on DACDAT. This is controlled using register bits DAC_BOOST [1:0]. To prevent clipping

at the DAC input, this function should not be used when the boosted DAC data is expected to be

greater than 0dBFS.

The digital interface volume is controlled as shown in Table 14.

ADDRESS

BIT

LABEL

DEFAULT

DESCRIPTION

R24 (18h)

Audio

Interface 0

10:9

DAC_BOOST

[1:0]

DAC Input Volume Boost

00 = 0dB

01 = +6dB (Input data must not

exceed -6dBFS)

10 = +12dB (Input data must not

exceed -12dBFS)

11 = +18dB (Input data must not

exceed -18dBFS)

Table 14 DAC Interface Volume Boost

WM8912 датащи(PDF) 31 Page - Cirrus Logic

WM8912 датащи(HTML) 31 Page - Cirrus Logic

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 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 ...More

датащи скачать

ссылки URL