WM8994ECSSLASHR datasheet(66/363 Pages) CIRRUS

66 / 363 page

WM8994

Rev 4.6

DIGITAL SIDETONE MIXING

There are two digital sidetone signal paths, STL and STR. The sidetone sources are selectable for

each path. The sidetone mixer outputs are inputs to the DAC signal mixers.

The following sources can be selected for sidetone path STL.



ADCL or DMICDAT1 (Left) channel



DMICDAT2 (Left) channel

The following sources can be selected for sidetone path STR.



ADCR or DMICDAT1 (Right) channel



DMICDAT2 (Right) channel

The sidetone signal sources are selected using STR_SEL and STL_SEL as described in Table 17.

Note that, when STR_SEL = 0 or STL_SEL = 0, and the respective ADC is enabled (for analogue

inputs), then the ADC data will be selected for applicable sidetone path.

ADDRESS

BIT

LABEL

DEFAULT

DESCRIPTION

R1569 (0621h)

Sidetone

STR_SEL

Select source for sidetone STR path

0 = ADCR / DMICDAT1 (Right)

1 = DMICDAT2 (Right)

STL_SEL

Select source for sidetone STL path

0 = ADCL / DMICDAT1 (Left)

1 = DMICDAT2 (Left)

Table 17 Digital Sidetone Mixing

DIGITAL SIDETONE VOLUME AND FILTER CONTROL

A digital volume control is provided for the digital sidetone paths. The associated register controls are

described in Table 18.

A digital high-pass filter can be enabled in the sidetone paths to remove DC offsets. This filter is

enabled using the ST_HPF register bit; the cut-off frequency is configured using ST_HPF_CUT. When

the filter is enabled, it is enabled in both digital sidetone paths.

Note that the sidetone filter cut-off frequency scales according to the sample rate of AIF1 or AIF2.

When AIF1CLK is selected as the SYSCLK source (SYSCLK_SRC = 0), then the ST_HPF cut-off

frequency is scaled according to the AIF1_SR register. When AIF2CLK is selected as the SYSCLK

source (SYSCLK_SRC = 1), then the ST_HPF cut-off frequency is scaled according to the AIF2_SR

ee “Clocking and Sample Rates” for further details of the system clocks and control

registers.

WM8994ECS/R Datenblatt(PDF) 66 Page - Cirrus Logic

WM8994ECS/R Datenblatt(HTML) 66 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

Datenblatt Download

Link URL