Chapter 3
Hardware
LittleBoard 735
Reference Manual
31
Audio Interface
The audio solution on the LittleBoard 735 is provided by the Realtek ALC203-LF audio CODEC. The chip
is defined by AC97 and is revision 2.2 compliant. The audio interface signals are supplied to the 26-pin
2mm connector (J9). Refer to the following list for the
Audio CODEC
(ALC203-LF) features.
•
Analog Mixer Dynamic Range 97dB (typ)
•
D/A Dynamic Range 89dB (typ) and A/D Dynamic Range 90dB (typ)
•
AC’97 Rev 2.1 compliant
•
High quality Sample Rate Conversion (SRC) from 4kHz to 48kHz
•
3D Sound circuitry and PC-Beep passthrough to Line Out while reset is held active low
•
True Line Level Output with volume control independent of Line Out
Table 3-13
describes the pin signals of the audio interface which uses 26 pins, 2 rows, odd/even sequence (1,
2) with 0.079" (2mm) pitch.
Note:
The shaded areas denote power or ground.
Table 3-13. Audio Interface Pin Signals (J9)
Pin #
Signal
Description
1
NC
Not connected (Video Audio In signal left channel)
2
VIDEO_GND
Video Audio ground
3
NC
Not connected (Video Audio In signal right channel)
4
CD_L
CD-ROM signal left channel
5
CD_GND
CD-ROM Audio ground
6
CD_R
CD-ROM signal right channel
7
LINE_IN_L
Line In signal left channel
8
LINE_IN_GND
Line In Audio ground
9
LINE_IN_R
Line In signal right channel
10
MIC1
Microphone In signal 1 or left channel
11
MIC_GND
Microphone Audio ground
12
MIC2
Microphone In signal 2 or right channel
13
MIC_REF
Microphone reference signal
14
NC/KEY
Not Connected - Key
15
PHONE_IN
Phone signal In
16
PHONE_GND
Phone Audio ground
17
MONO_OUT
Monaural signal Out
18
MONO_GND
Monaural Audio ground
19
+AOUT_L
+ Audio Out signal Left channel
20
-AOUT_L
- Audio Out Left ground
21
+AOUT_R
+ Audio Out signal Right channel
22
-AOUT_R
- Audio Out Right ground
23
GND
Audio Ground (tied to all audio grounds)
24
HP_L
Headphone signal Left channel
25
HP_R
Headphone signal Right channel
26
NC
Not Connected (Headphone In)
Summary of Contents for LittleBoard 735
Page 1: ...LittleBoard 735 Single Board Computer Reference Manual P N 50 1Z020 1000 ...
Page 6: ...Contents vi Reference Manual LittleBoard 735 ...
Page 46: ...Chapter 3 Hardware 40 Reference Manual LittleBoard 735 ...
Page 50: ...Chapter 4 BIOS Setup 44 Reference Manual LittleBoard 735 ...
Page 52: ...Appendix A Technical Support 46 Reference Manual LittleBoard 735 ...