92HD91 Datasheet, PDF (43/298 Pages) Integrated Device Technology – SINGLE CHIP PC AUDIO SYSTEM

92HD91
SINGLE CHIP PC AUDIO SYSTEM, CODEC+SPEAKER AMPLIFIER+CAPLESS HP+LDO
Figure 16. Aux Audio Record when the System is Docked with the System Microphone Plugged In
Record Analog Mic
D-MIC
MIC
HP
DM
DAC
A
B
S
HD Audio Interface
S
E
F
I2S
CODEC
I2S
Routing
Dock
HP
MIC
SPKR
D
EQ
S
NA
C
PC
Beep
Aux Audio
Module
Filter
EC
Figure 17. Aux Audio Record when the System is Docked with the Dock Microphone Plugged In
Record Dock Mic
D-MIC
MIC
HP
DM
DAC
A
B
S
HD Audio Interface
S
E
F
I2S
CODEC
I2S
Routing
Dock
HP
MIC
SPKR
D
EQ
S
NA
C
PC
Beep
Filter
EC
Aux Audio
Module
2.26.8. EAPD
Since the Aux Audio mode overrides the default behavior but not the actual port settings when in
reset, the logical state of the EAPD pin must be overridden as well. When Aux Audio mode is
enabled and the part is in reset as described above, the logical state of EAPD will be 1 (External
Amplifier Powered Up) unless held low by an external circuit. This ensures that audio pass-thru and
analog PC_Beep will be supported.
2.26.9. Analog PC_Beep
Analog PC_Beep is supported in Aux Audio mode. By default, analog PC_Beep is disabled but may
be enabled due to Beep pass-thru support in reset (see the PC_Beep section). If the CODEC is pro-
grammed to enable analog PC_Beep and Aux Audio mode is enabled, the next time reset is
asserted, the analog PC_Beep pin will be mixed at each of the active outputs.
IDT™ CONFIDENTIAL
43
©2009 INTEGRATED DEVICE TECHNOLOGY, INC.
V 1.2 1/12
92HD91