92hd89d Integrated Device Technology, 92hd89d Datasheet - Page 33

• Manufacturer Part Number: 92hd89d
• Description: Eight Channel Hd Audio Codec Low Power Optimized For Ecr15b And Eup
• Manufacturer: Integrated Device Technology

92HD89D
Eight channel HD Audio codec optimized for low power
©2009 INTEGRATED DEVICE TECHNOLOGY, INC.
EAPD PIN
MODE 1:0
HP SD
HP SD MODE
HP SD INV
Control Flag
2.18. EAPD
MODE1
HP SD
0
0
1
1
0
0
0
0
0
0
Defines if EAPD pin is used as input, output, or bi-directional port (Open Drain)
0 = Amp controlled by EAPD pin only (default) / 1 = Amp controlled by power state (pin and FG) only
0 = Amp will mute when disabled. (default) / 1 = Amp will shut down (enter a low power state) when disabled
0 = AMP will power down (or mute) when EAPD pin is low (default) / 1 = Amp will power down (or mute) when EAPD
pin is high.
The EAPD pin (pin 47) also supports SPDIF_OUT, SPDIF_IN, and GPIO functions. The pin defaults
to EAPD after power on reset and will remain in EAPD mode until either GPIO is enabled for pin 47
or the port I/O is enabled as an input to support SPDIF_IN or an output to support SPDIF_OUT.
Although named External Amplifier Power Down (EAPD) by the HD Audio specification, this pin
operates as an external amplifier power up signal. The EAPD value is reflected on the EAPD pin; a 1
causes the external amplifier to power up (equivalent to D0), and a 0 causes it to power down
(equivalent to D3.) When the EAPD value = 1, the EAPD pin must be placed in a state appropriate to
the current power state of the associated Pin Widget even though the EAPD value (in the register)
may remain 1. The pin defaults to an open-drain configuration (an external pull-up is recommended.)
Per the HD Audio specification and ECR15b, multiple ports may control EAPD. The EAPD pin
assumes the highest power state of all the the EAPD bits in all of the pin complexes. The default
value of EAPD is 1 (powered on), but the FG power state will override and the pin will be low.
Vendor specific verbs are available to configure this pin. These verbs retain their values across link
and single function group resets but are set to their default values by power on reset:
MODE0
HP SD
MODE
0
1
0
1
0
0
0
0
1
1
EAPD Pin Function
HP SD INV
Table 14. Headphone Amp Enable Configuration
Open Drain I/O
CMOS Output
CMOS Input
CMOS Input
0
0
1
1
0
0
EAPD Pin
State
0
1
0
1
0
1
External signal controls internal amps. EAPD bit in pin widget ignored
External signal controls internal amps. EAPD bit in pin widget ignored
Value at pin is wired-AND of EAPD bit and external signal. (default)
33
Amplifier is mute (default
Amplifier is active
Amplifier is active
Amplifier is mute
Amplifier is in a low power state
Amplifier is active
Description
Value of EAPD bit in pin widget is forced at pin
Headphone Amp State
Description
1
)
V1.0 04/10
92HD89D