STAC9227 Datasheet, PDF (23/237 Pages) Integrated Device Technology – 8-CHANNEL HIGH DEFINITION AUDIO CODEC

STAC9227/9228/9229/9230
8-CHANNEL HIGH DEFINITION AUDIO CODEC
PC AUDIO
3.2.
Impedance Sense
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 SigmaTel
Extranet for more information.
Table 1: Impedance Sense
Bins Return Hex Code Impedance Level (Ohms)
General Device Detected
000b
0064h
Impedance < 300 Ω
Passive Speakers, Headset Speakers
001b
012Ch
Impedance = 300 Ω +/- 25%
Some Headset Speakers
010b
028Ah
300 Ω > Impedance < 1275 Ω
Some Microphones
011b
03E8h
Impedance = 1275 Ω +/- 25%
Microphones
100b
07D0h
1275 Ω > Impedance < 2000 Ω
Microphones
101b
0BB8h
Impedance = 2000 Ω +/- 25%
Amplified Speakers
110b
2710h
> 2000 Ω
Amplified Speakers, Line In
111b
2710h
> 2000 Ω
Amplified Speakers, Line In
3.3.
SPDIF Input
SPDIF IN can operate at 44.1 KHz, 48 KHz and 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.
3.4.
SPDIF Output
SPDIF Ouput can operate at 44.1 KHz, 48 KHz, 88.2 KHz, and 96 KHz, as defined in the Intel High
Definition Audio Specification, with resolutions up to 24 bits. This insures compatibility with all con-
sumer audio gear and allows for convenient integration into home theater systems and media center
PCs.
IDT™ 8-CHANNEL HIGH DEFINITION AUDIO CODEC
23
IDT CONFIDENTIAL
STAC9227/9228/9229/9230V 1.0 MARCH 2007