MAX9888 Maxim Integrated Products, MAX9888 Datasheet - Page 69

• Manufacturer Part Number: MAX9888
• Description: Stereo Audio CODEC
• Manufacturer: Maxim Integrated Products

DataSheet.in
Table 8. Sidetone Register
The IC includes two separate playback signal paths and
one record signal path. Digital audio interface 1 (DAI1)
is used to transmit the recorded stereo audio signal and
receive a stereo audio signal for playback. Digital audio
interface 2 (DAI2) is used to receive a second stereo
audio signal. Use DAI1 for all full-duplex operations and
for all voice signals. Use DAI2 for music and to mix two
playback audio signals. The digital audio interfaces are
separate from the audio ports to enable either interface
to communicate with any external device connected to
the audio ports.
Each audio interface can be configured in a variety of
formats including left justified, I
sion multiplexed (TDM). TDM mode supports up to 4
mono audio slots in each frame. The IC can use up to
REGISTER
0x2A
BIT
7
6
4
3
2
1
0
NAME
Digital Audio Interfaces
DSTS
DVST
2
S, PCM, and time divi-
Sidetone Source
Selects which ADC output is fed back as sidetone. When mixing the left and right ADC
outputs, each is attenuated by 6dB to prevent full-scale signals from clipping.
00 = Sidetone disabled
01 = Left ADC
10 = Right ADC
11 = Left + Right ADC
Sidetone Level
Adjusts the sidetone signal level. All levels are referenced to the ADC’s full-scale output.
VALUE
with FLEXSOUND Technology
0x0A
0x0B
0x0C
0x0D
0x0E
0x00
0x01
0x02
0x03
0x04
0x05
0x06
0x07
0x08
0x09
0x0F
Sidetone disabled
2 mono slots per interface, leaving the remaining two
slots available for another device. Table 9 shows how to
configure the device for common digital audio formats.
Figures 16 and 17 show examples of common audio
formats. By default, SDOUTS1 and SDOUTS2 are set
high impedance when the IC is not outputting data to
facilitate sharing the bus. Configure the interface in TDM
mode using only slot 1 to transmit and receive mono
PCM voice data.
The IC’s digital audio interfaces support both ADC to
DAC loop-through and digital loopback. Loop-through
allows the signal converted by the ADC to be routed
to the DAC for playback. The signal is routed from the
record path to the playback path in the digital audio
interface to allow the IC’s full complement of digital
signal processing to be used. Loopback allows digital
LEVEL (dB)
-10.5
-12.5
-14.5
-16.5
-18.5
-20.5
-22.5
-24.5
-26.5
-28.5
-0.5
-2.5
-4.5
-6.5
-8.5
Stereo Audio CODEC
DESCRIPTION
VALUE
0x1C
0x1D
0x10
0x11
0x12
0x13
0x14
0x15
0x16
0x17
0x18
0x19
0x1A
0x1B
0x1E
0x1F
LEVEL (dB)
-30.5
-32.5
-34.5
-36.5
-38.5
-40.5
-42.5
-44.5
-46.5
-48.5
-50.5
-52.5
-54.5
-56.6
-58.5
-60.5
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