cx25840 Conexant Systems, Inc., cx25840 Datasheet - Page 32

• Manufacturer Part Number: cx25840
• Description: Video Decoder And Broadcast Audio
• Manufacturer: Conexant Systems, Inc.

Detailed Functional Description
3.2.5
3-6
Configuring for S-Video and Sound IF Audio
Table 3-8. AFE Configuration for S-Video and Sound IF Input
INPUT_MODE
CLAMP_SEL_CH{1}
CLAMP_SEL_CH{2}
CLAMP_SEL_CH{3}
DUAL_MODE_ADC2
HALF_BW_CH{2}/3
DROOP_COMP_CH{2}/3
CLAMP_EN_CH{2}/3
AUD_IN_SEL
VGA_SEL_CH{2}/3
In this scenario, the input mux is used to route S-Video and the Sound IF audio
source. In this case, all three channels of the AFE are used. As shown in
luma portion of the S-Video input must be routed to CH{1}, the chroma portion of the
S-Video input must be routed to CH{3}, and the Sound IF audio of the tuner input
must be routed to CH{2}.
Table 3-8
operation.
Table 3-7. Example S-Video and 2nd IF Mux Configuration
Control Bits
Active Input
2nd IF 1
2nd IF 2
summarizes the state of the AFE control bits for S-Video and Sound IF
Figure 3-2
Y1
C1
Y2
C1
shows the S-Video and Sound IF Audio Interface.
CH{3} = 0 (Sound IF input on analog CH2)
CH{3} = 0 (Sound IF input on analog CH2)
CH{3} = 0 (Sound IF input on analog CH2)
CH{3} = 0 (Sound IF input on analog CH2)
Conexant
Control Bits
CH{2} = 0 (Chroma input on analog CH3)
CH{2} = 0 (Chroma input on analog CH3)
CH{2} = 0 (Chroma input on analog CH3)
CH{2} = 0 (Chroma input on analog CH3)
CH{1}_SRC
CH{3}_SRC
CH{2}_SRC
CH{1}_SRC
CH{3}_SRC
CH{2}_SRC
Value
10
0
1
0
1
1
Bit Value
000
001
00
00
01
01
CX25840/1/2/3 Data Sheet
Table
3-7, the
102284B
8/3/05