92hd73e Integrated Device Technology, 92hd73e Datasheet - Page 28

• Manufacturer Part Number: 92hd73e
• Description: Ten Channel Hd Audio Codec Premium Wlp 3/4 Compliant
• Manufacturer: Integrated Device Technology

TEN CHANNEL HD AUDIO CODEC, PREMIUM WLP 3/4 COMPLIANT
92HD73E
TEN CHANNEL HD AUDIO CODEC, PREMIUM WLP 3/4 COMPLIANT
1.4.14. PC-Beep
1.4.15. Headphone Drivers
92HD73E supports both analog and digital PC_Beep functions.
1.4.14.1. Analog PC-Beep
92HD73E does not support automatic routing of the PC_Beep pin to all outputs when the link is in
reset. Analog PC-Beep may be supported during Link Reset if the mixer is manually configured for
pass-thru. Otherwise, Reset# must be high and Bit_Clk active.
The default values for the vendor specific verb (7EE/FEE in AFG) associated with Analog PC-Beep
are:
•
•
Analog PC-Beep is supported in D3, but may be attenuated or distorted depending on the load-
impedance on the port. Line outputs can drive 10K ohm loads in D3 at 1Vrms, but will be current lim-
ited when driving lower impedance loads. Enabling or disabling analog PC-Beep may cause a click
or pop sound.
1.4.14.2. Digital PC-Beep
This block uses an 8-bit divider value to generate the PC beep from the 48kHz Azalia sync pulse.
The digital PC_Beep block generates the beep tone on all Pin Complexes that are currently config-
ured as outputs. The HD Audio spec states that the beep tone frequency = (48kHz HD Audio SYNC
rate) / (4*Divider), producing tones from 47 Hz to 12 kHz (logarithmic scale). Other audio sources
are disabled when digital PC_Beep is active.
It should be noted that digital PC Beep is disabled if the divider = 00h.
This product implements a +3dBV output option on headphone capable ports. (HP output and line
output levels are defined as 1Vrms at this time with an option to enable +3dBV FSOV using a vendor
specific verb.) The Microsoft Windows Logo Program allows up to the equivalent of 100ohms in
series. However, an output level of +3dBV at the pin is required to support 300mV at the jack with a
32ohm load and 1V with a 320 ohm load. Microsoft allows device and system manufactures to limit
output voltages to address EU safety requirements. (WLP 3.09 - please refer to the latest Windows
Logo Program requirements from Microsoft.) 92HD73E, however, requires external components
(series resistors) to limit the output voltage to 150mV with a 32 ohm load or secure software limiting
by restricting DAC and mixer gain ranges.
Although 3 Headphone amplifiers are present, only two may be used simultaneously.
Performance will degrade when driving more than one set of headphones. Only one set of head-
phones (32 ohm nominal) may be connected to a headphone capable port.
Enable = 0h (Analog PC-Beep disabled - mute)
volume = 3h (0dB)
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92HD73E
PC AUDIO
V 1.0 03/08