92hd75b Integrated Device Technology, 92hd75b Datasheet - Page 15

• Manufacturer Part Number: 92hd75b
• Description: Four Channel Hd Audio Codec
• Manufacturer: Integrated Device Technology

4-CHANNEL HD AUDIO CODECS OPTIMIZED FOR LOW POWER
92HD75B
4-CHANNEL HD AUDIO CODECS OPTIMIZED FOR LOW POWER
1.4.6.
1.4.7.
1.4.8.
1.4.9.
Mono Output
The MONO Output has an independent mute (see the Widget listing for details). The MONO Output
derives its input from the output of the summing node after the mono mux. The following sources are
available for the mono pin:
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The stereo inputs are scaled by -6dB and then summed to provide an output that is the average of
the two inputs. The full scale output at mono out is designed to be about 0dBV. It is not possible to
adjust to a +3dBV output level.
Mono out and Analog PC Beep share a pin. If legacy Analog PC Beep input and mono out are
required, Port E can be used as an optional Analog PC Beep Input.
Input Multiplexers
92HD75B implements 2 port input multiplexers. These multiplexers incorporate the microphone
boost function (0, 10dB, 20dB, 30dB, and 40dB gain) as an output amp and allow a preselection of
one of three possible inputs:
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NOTE: Changing the Input multiplexer setting will affect the ADC. This may present a negative user
experience and must be exposed carefully to prevent problems. 40dB boost is implemented but the
only 0-30dB gain steps are reported.
ADC Multiplexers
92HD75B implements 2 ADC input multiplexers. These multiplexers incorporate the ADC record
gain function (0 to +22.5dB gain in 1.5dB steps) as an output amp and allow a preselection of one of
four possible inputs:
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Power Management
The following table describes what functionality is active in each power state
The D3-default state is available for HD Audio compliance. The programmable values, exposed via
vendor-specific settings, are under the IDT Device Driver control for further power reduction.
DAC0 Output: When enabled (by using port connection list), both DAC0 Outputs are summed
together.
DAC1 Output: When enabled (by using port connection list), both DAC1 Outputs are summed
together.
Input Mixer: When enabled (by using mono mix connection list and DAC mixer), both mixer out-
puts are summed together.
Port B
Port C
Port E
DMIC 0
DMIC1 (48QFN package only)
InPortMux (ADC0 selects inport0_mux / ADC1 selects inport1_mux)
Mixer output
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92HD75B
PC AUDIO
V 1.0 01-09