Analog Devices ADV8003, Руководство по оборудованию

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ADV8003 Hardware Manual
Rev. B, August 2013 316
Filter Pass-Band Ripple (dB) 1 3 dB Bandwidth (MHz) 2
Luma Notch PAL 0.1 3.1/5.6/6.4
Luma SSAF 0.04 6.45
Luma CIF 0.127 3.02
Luma QCIF Monotonic 1.5
Chroma 0.65 MHz Monotonic 0.65
Chroma 1.0 MHz Monotonic 1
Chroma 1.3 MHz 0.09 1.395
Chroma 2.0 MHz 0.048 2.2
Chroma 3.0 MHz Monotonic 3.2
Chroma CIF Monotonic 0.65
Chroma QCIF Monotonic 0.5
1 Pass-band ripple is the maximum fluctuation from the 0 dB response in the pass band, measured in decibels. The pass band is defined to have 0 Hz to fc (Hz)
frequency limits for a low-pass filter and 0 Hz to f1 (Hz), and f2 (Hz) to infinity for a notch filter, where fc, f1, and f2 are the −3 dB points.
2 3 dB bandwidth refers to the −3 dB cutoff frequency.
The luma filter supports several different frequency responses, including two low-pass responses, two notch responses, an extended
(SSAF) response with or without gain boost attenuation, a CIF response, and a QCIF response. These can be configured using
luma_filter_sel[2:0] .
luma_filter_sel[2:0]
, Encoder Map, Address 0xE480[4:2]
This signal is used to configure the luma filters for SD data.
Function
luma_filter_sel[2:0] Description
000 LPF NTSC
001 LPF PAL
010 Notch NTSC
011 Notch PAL
100  SSAF Luma
101 Luma CIF
110 Luma QCIF
111 Reserved
If SD SSAF gain is enabled, there are 13 response options in the −4 dB to +4 dB range. The desired response can be programmed using
register 0xA2. The variation in frequency responses is shown in
Figure 106 , Figure 107 , and Figure 108 . The registers required for enabling
and controlling the SSAF filter gain are described below.
FREQUENCY (MHz)
4
7
M
AG
NI
T
UDE
(
d
B)
2
–2
–6
–8
–12
0
–4
5
–10
6 0 1 2 3 4
06398-
036
Figure 106: SD Luma SSAF Filter, Programmable Responses