STAC9271 Datasheet, PDF (22/223 Pages) Integrated Device Technology – 10-CHANNEL HIGH DEFINITION AUDIO CODEC

STAC9271/9272/9273/9274
10-CHANNEL HIGH DEFINITION AUDIO CODEC
PC AUDIO
Impedance Sense is accomplished by on-chip circuitry that measures the impedance at the pin of
the chip and compares it to internal reference impedance. Below is a table that contains the bin infor-
mation and codes returned when the pin widget impedance field in the Port Pin Sense widget is
read. Please note that even under the best conditions, there is no method to guarantee 100%
impedance sensing due to variations in external circuitry and impedance overlap of devices that can
be plugged into a jack. The impedance sense table reflects both standard Line Out and Headphone
output drivers. Please reference the HD Audio Universal Jack Application Note on the IDT Extranet
for more information.
Bins Return Hex Code
000b
0064h
001b
012Ch
010b
028Ah
011b
03E8h
100b
07D0h
101b
0BB8h
110b
2710h
111b
2710h
Table 2: Impedance Sense
Impedance Level (Ohms)
General Device Detected
Impedance < 300
Passive Speakers, Headset Speakers
Impedance = 300 +/- 25%
Some Headset Speakers
300 > Impedance < 1275
Some Microphones
Impedance = 1275 +/- 25%
Microphones
1275 > Impedance < 2000
Microphones
Impedance = 2000 +/- 25%
Amplified Speakers
> 2000
Amplified Speakers, Line In
> 2000
Amplified Speakers, Line In
3.2. SPDIF Input
SPDIF IN can operate at 44.1 KHz, 48 KHz or 96 KHz and implements internal Jack Detect.
A sophisticated digital PLL allows automatic rate detection and accurate data recovery. The ability to
accept consumer SPDIF voltage levels directly eliminates the need for costly external receiver ICs.
Advanced features such as record slot select and SPDIF_IN routing to the DAC allows for simulta-
neous record and play.
IDT™ 10-CHANNEL HIGH DEFINITION AUDIO CODEC
22
IDT CONFIDENTIAL
STAC9271/9272/9273/9274 V 1.0 MARCH2007