Audio Codec '97

AC ‘97 Component Specification Revision 2.3 Rev 1.0
104
RESET, SYNC, & SDATA_OUT 1 Codec 2 Codecs 3 Codecs 4 Codecs
Controller Output Pin Capacitance 7.5pF 7.5pF 7.5pF 7.5pF
Motherboard Trace Capacitance (Note 1) 30pF 30pF 30pF 30pF
Codec Input Pin Capacitance (Note 2) 7.5pF 15pF 22.5pF 30pF
Riser Connector Capacitance 2.5pF 2.5pF 2.5pF 2.5pF
CNR Trace Capacitance (Notes 3 & 4) 0pF 7.5pF 12.5pF 15pF
Total Capacitance driven by output pin 47.5pF 62.5pF 75pF 85pF
Note 1 – Motherboard Trace Capacitance assumed to be 12 inches of trace length at ~2.5pF per inch
Note 2 – Codec Input Pin Capacitance based off of 7.5pF per input pin, as specified in AC ‘97 2.3
Note 3 – CNR Trace Capacitance assumed to be 2.5pF per inch with 3 inches for 2
nd
Codec, 5 inches for 3
rd
Codec, and 6 inches
for 4
th
Codec
Note 4 – 1
st
Codec is assumed to be on the motherboard
Table 62. AC-link Controller output pin driver loading
BIT_CLK 1 Codec 2 Codecs 3 Codecs 4 Codecs
Codec Output Pin Capacitance 7.5pF 7.5pF 7.5pF 7.5pF
Motherboard Trace Capacitance (Note 1) 30pF 30pF 30pF 30pF
Codec Input Pin Capacitance (Note 2 & 4) 0pF 7.5pF 15pF 22.5pF
Controller Input Pin Capacitance 7.5pF 7.5pF 7.5pF 7.5pF
Riser Connector Capacitance 2.5pF 2.5pF 2.5pF 2.5pF
CNR Trace Capacitance (Notes 3 & 4) 0pF 7.5pF 12.5pF 15pF
Total Capacitance driven by output pin 47.5pF 62.5pF 75pF 85pF
Note 1 – Motherboard Trace Capacitance assumed to be 12 inches of trace length at ~2.5pF per inch
Note 2 – Codec Input Pin Capacitance based off of 7.5pF per input pin, as specified in AC ‘97 2.3
Note 3 – CNR Trace Capacitance assumed to be 2.5pF per inch with 3 inches for 2
nd
Codec, 5 inches for 3
rd
Codec,
and 6 inches for 4
th
Codec
Note 4 – 1
st
Codec is assumed to be on the motherboard and is the Codec driving the BIT_CLK signal
Table 63. AC-link Codec BIT_CLK Output pin driver loading
SDATA_IN 1 Codec 2 Codecs 3 Codecs 4 Codecs
Codec Output Pin Capacitance 7.5pF 7.5pF 7.5pF 7.5pF
Motherboard Trace Capacitance (Note 1) 30pF 30pF 30pF 30pF
Controller Input Pin Capacitance 7.5pF 7.5pF 7.5pF 7.5pF
Riser Connector Capacitance 2.5pF 2.5pF 2.5pF 2.5pF
CNR Trace Capacitance (Notes 2 & 3) 0pF 7.5pF 12.5pF 15pF
Total Capacitance driven by output pin 47.5pF 55pF 60pF 62.5pF
Note 1 – Motherboard Trace Capacitance assumed to be 12 inches of trace length at ~2.5pF per inch
Note 2 – CNR Trace Capacitance assumed to be 2.5pF per inch with 3 inches for 2
nd
Codec, 5 inches for 3
rd
Codec,
and 6 inches for 4
th
Codec
Note 3 – 1
st
Codec is assumed to be on the motherboard and is the Codec driving the BIT_CLK signal
Table 64. AC-link Codec SDATA_IN Output pin driver loading
10. Analog Performance Characteristics
(Test conditions unless otherwise noted: T
ambient
= 25
0
C; DVdd = 3.3 V +/- 5%; AVdd = 5.0 V +/- 5%; 1 kHz input