ADV7180
IF FILTER COMPENSATION
IFFILTSEL[2:0], IF Filter Select, Address 0xF8 [2:0]
The IFFILTSEL[2:0] register allows the user to compensate for
SAW filter characteristics on a composite input, as would be
observed on tuner outputs. Figure 29 and Figure 30 show IF
filter compensation for NTSC and PAL, respectively.
The options for this feature are as follows:
•
•
•
Bypass mode
NTSC—consists of three filter characteristics
PAL—consists of three filter characteristics
6
4
2
AMPLITUDE (dB)
IF COMP FILTERS NTSC ZOOMED AROUND FSC
0
–2
–4
–6
–8
–10
–12
2.0
05700-053
See Table 103 for programming details.
2.5
3.0
3.5
4.0
FREQUENCY (MHz)
4.5
5.0
Figure 29. NTSC IF Filter Compensation
6
4
2
AMPLITUDE (dB)
IF COMP FILTERS PAL ZOOMED AROUND FSC
0
–2
–4
–6
–8
3.0
3.5
4.0
4.5
5.0
FREQUENCY (MHz)
5.5
6.0
Figure 30. PAL IF Filter Compensation
Rev. A | Page 40 of 112
05700-054
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