Analog Devices ADV8005, Hardware Reference Manual

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ADV8005 Hardware Reference Manual UG-707
chroma_filter_sel[2:0] , Encoder Map, Address 0xE480[7:5]
This signal is used to configure the chroma filters for SD data.
Function
chroma_filter_sel[2:0] Description
000 (default) 1.3MHz
001 0.65MHz
010 1MHz
011 2MHz
100 Reserved
101 Chroma CIF
110 Chroma QCIF
111 3MHz
In addition to the chroma filters listed with
chroma_filter_sel[2:0] , there is an SSAF filter that is specifically designed for the color difference
component outputs, Pr and Pb. This filter has a cutoff frequency of ~2.7 MHz and a gain of –40 dB at 3.8 MHz. Refer to Figure 115 for more
details. To enable this filter, wide_uv_filt should be set to 1.
Figure 115: PrPb SSAF Filter
wide_uv_filt , Encoder Map, Address 0xE482[0]
This bit is used to enable the SSAF filter for PrPb SD data.
Function
wide_uv_filt Description
1 (default) Enabled
0 Disabled
If this filter is disabled, one of the chroma filters shown in Table 73 can be selected and used for the CVBS or luma/chroma signal.
7.4.7.2. ED/HD Filters
The ADV8005 encoder core also includes a sinc compensation filter designed to counter the effect of sinc roll-off in DAC 1, DAC 2, and DAC
3 while operating in ED/HD mode. The benefit of the filter is illustrated in Figure 116 and Figure 117 which show the effect of the filter when
enabled and disabled. This filter is enabled by default but can be disabled using sinc_filt_df_en .
FREQUENCY (MHz)
0
G
AI
N (
d
B)
–10
–30
–50
–60
–20
–40
6 5 4 3 2 1 0
EXTENDED (SSAF) PrPb FILTER MODE
06398-
066
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