92HD87 Datasheet, PDF (29/204 Pages) Integrated Device Technology – SINGLE CHIP PC AUDIO SYSTEM

92HD87
SINGLE CHIP PC AUDIO SYSTEM, CODEC+STEREO SPEAKER AMPLIFIER+CAPLESS HP+LDO
unless EAPD is forced low or D3cold has been set. The Enable bit in the Aux Audio vendor spe-
cific verb is provided so firmware or other software can disable Aux Audio support and allow
stopping the HD Audio bus when an OS is in an active state. The default value of this bit is deter-
mined by a bond option and may be determined by reading the device ID. This bit only returns to
its default value when a power on reset event is generated.
2.22.2. “Playback Path” Port Behavior
Port F (Aux Audio In) input is routed to Port D (“internal speakers”) and Ports A&B (system head-
phone jacks) through the analog mixer.
2.22.3.
When Port E presence detect = 0
• Presence detect for Port E = 0 (nothing plugged in)
• Port F, the “Aux Audio In”, input is routed to Port A, B, or D when that port is active.
• If either Port A or Port B is in use (port presence detect = 1), Port D, internal speakers, will be
inactive (off)
• To save power, the power supply for Port B will be active only if Port B is in use (Port B presence
detect = 1).
• If neither Port A nor Port B is in use (port presence detect = 0), Port D, internal speakers, will be
active and ports A and B will be inactive.
• EAPD must not be forced low due to the dock being absent or high when a dock is present.
EAPD is used to indicate if AUX Audio Mode is in use.
2.22.4.
When Port E presence detect = 1
• Presence detect for Port E = 1 (something plugged in)
• Port F, the “Aux Audio In”, input is routed to Ports A, B
• Port D is disabled
• If either Port A or Port B is in use (port presence detect = 1), that port will be enabled and output
the audio entering Port F.
• To save power, the power supply for Port B will be active only if Port B is in use (Port B presence
detect = 1).
• If neither Port A nor Port B is in use (port presence detect = 0), ports A and B will be inactive
and the audio on Port F will play through the docked device (assuming that the docked device
signals that headphones are plugged into the device by using the Port E presence detect.)
• EAPD must not be forced low due to the dock being absent or high when a dock is present.
EAPD is used to indicate if AUX Audio Mode is in use.
IDT CONFIDENTIAL
29
©2009 INTEGRATED DEVICE TECHNOLOGY, INC.
V 0.995 01/11
92HD87