WM8993 datasheet(45/229 Pages) WOLFSON

45 / 229 page

Production Data

WM8993

PD, November 2010, Rev 4.0

ANALOGUE TO DIGITAL CONVERTER (ADC)

The WM8993 uses stereo 24-bit, 128x oversampled sigma-delta ADCs. The use of multi-bit feedback

and high oversampling rates reduces the effects of jitter and high frequency noise. An oversample

rate of 64x can also be supported - see “Clocking and Sample Rates” for details. The ADC full scale

input level is proportional to AVDD1 - see “Electrical Characteristics”. Any input signal greater than

full scale may overload the ADC and cause distortion.

The ADCs are enabled by the ADCL_ENA and ADCR_ENA register bits.

ADDRESS

BIT

LABEL

DEFAULT

DESCRIPTION

R2 (02h)

Power

Management (2)

ADCL_ENA

Left ADC Enable

0 = ADC disabled

1 = ADC enabled

ADCR_ENA

Right ADC Enable

0 = ADC disabled

1 = ADC enabled

Table 9 ADC Enable Control

ADC DIGITAL VOLUME CONTROL

The output of the ADCs can be digitally amplified or attenuated over a range from -71.625dB to

+17.625dB in 0.375dB steps. The volume of each channel can be controlled separately. The gain for

a given eight-bit code X is given by:

0.375

× (X-192) dB for 1 ≤ X ≤ 239;

MUTE for X = 0

+17.625dB for 239

≤ X ≤ 255

The ADC_VU bit controls the loading of digital volume control data. When ADC_VU is set to 0, the

ADCL_VOL or ADCR_VOL control data will be loaded into the respective control register, but will not

actually change the digital gain setting. Both left and right gain settings are updated when a 1 is

written to ADC_VU. This makes it possible to update the gain of both channels simultaneously.

ADDRESS

BIT

LABEL

DEFAULT

DESCRIPTION

R15 (0Fh)

Left ADC

Digital Volume

ADC_VU

N/A

ADC Volume Update

Writing a 1 to this bit will cause left

and right ADC volume to be updated

simultaneously

7:0

ADCL_VOL

[7:0]

1100_0000

(0dB)

Left ADC Digital Volume

00h = MUTE

01h = -71.625dB

… (0.375dB steps)

EFh = +17.625dB

(See Table 11 for volume range)

R16 (10h)

Right ADC

Digital Volume

ADC_VU

N/A

ADC Volume Update

Writing a 1 to this bit will cause left

and right ADC volume to be updated

simultaneously

7:0

ADCR_VOL

[7:0]

1100_0000

(0dB)

Right ADC Digital Volume

00h = MUTE

01h = -71.625dB

… (0.375dB steps)

EFh = +17.625dB

(See Table 11 for volume range)

Table 10 ADC Digital Volume Control

WM8993 датащи(PDF) 45 Page - Wolfson Microelectronics plc

WM8993 датащи(HTML) 45 Page - Wolfson Microelectronics plc

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