WM8903LGEFK/RV Wolfson Microelectronics, WM8903LGEFK/RV Datasheet - Page 55

• Manufacturer Part Number: WM8903LGEFK/RV
• Description: Audio CODECs ULTRA LOW PWR HI FI CODEC
• Manufacturer: Wolfson Microelectronics

Specifications of WM8903LGEFK/RV

• Audio Codec Type: Stereo Codec
• No. Of Adcs: 2
• No. Of Dacs: 2
• No. Of Input Channels: 6
• No. Of Output Channels: 8
• Adc / Dac Resolution: 24bit
• Sampling Rate: 96kHz
• Operating Temperature Range: -40°C To +85°C
• Rohs Compliant: Yes
• Adcs / Dacs Signal To Noise Ratio: 96dB
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

Production Data
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Table 26 DAC Interface Volume Boost
DIGITAL SIDETONE
Digital sidetone mixing (from ADC output into DAC input) is available when ADCs and DACs are
operating at the same sample rate. Digital data from either left or right ADC can be mixed with the
audio interface data on the left and right DAC channels. Sidetone data is taken from the ADC
high-pass filter output, to reduce low frequency noise in the sidetone (e.g. wind noise or mechanical
vibration).
When using the digital sidetone, it is recommended that the ADCs are enabled before un-muting the
DACs to prevent pop noise. The DAC volumes and sidetone volumes should be set to an appropriate
level to avoid clipping at the DAC input.
When digital sidetone is used, it is recommended that the Charge Pump operates in Register Control
mode only (CP_DYN_PWR = 0). See “Charge Pump” for details.
The digital sidetone is controlled as shown in Table 27.
Table 27 Digital Sidetone Control
R24 (18h)
Audio
Interface 0
R32 (20h)
DAC Digital 0
REGISTER
REGISTER
ADDRESS
ADDRESS
10:9
11:8
BIT
BIT
7:4
3:2
1:0
DAC_BOOST
[1:0]
ADCL_DAC_SV
OL [3:0]
ADCR_DAC_SV
OL [3:0]
ADC_TO_DACL
[1:0]
ADC_TO_DACR
[1:0]
LABEL
LABEL
DEFAULT
DEFAULT
0000
0000
00
00
00
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)
Left Digital Sidetone Volume
0000 = -36dB
0001 = -33dB
(… 3dB steps)
1011 = -3dB
11XX = 0dB
(See Table 28 for volume range)
Right Digital Sidetone Volume
0000 = -36dB
0001 = -33dB
(… 3dB steps)
1011 = -3dB
11XX = 0dB
(See Table 28 for volume range)
Left DAC Digital Sidetone Source
00 = No sidetone
01 = Left ADC
10 = Right ADC
11 = Reserved
Right DAC Digital Sidetone Source
00 = No sidetone
01 = Left ADC
10 = Right ADC
11 = Reserved
PD, Rev 4.0, September 2010
DESCRIPTION
DESCRIPTION
WM8903
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