AK8826 Datasheet, PDF (48/157 Pages) Asahi Kasei Microsystems – HD/SD Multi Format Video Encoder with 3ch DAC

Over-sampling filter with aperture-effect compensation for Luminance (1080i/720P)
[AK8826VN]
AK8826 equips the aperture-effect compensation filter for Luminance Signal.
This filter can be set with HDAFT[1:0]-bit of HD Block Miscellaneous Control Register [Sub Address 0x0A].
Compensation degree can be set with this register-bit. “Mode 0” is less compensation and “Mode 3” is more compensation.
HD Block Miscellaneous Control Register
Sub Address 0x0A
bit 7
bit 6
bit 5
Reserved
Reserved STD770_2C
0
0
0
bit 4
bit 3
HDCEA805B CCWSSSUE
Default Value
0
0
bit 2
Reserved
0
default Value 0x00
bit 1
bit 0
HDAFLT1
HDAFLT0
0
0
HDAFLT[1:0]-bit
00
01
10
11
Filter Mode
MODE0
MODE1
MODE2
MODE3
Note
X2 Over-sampling Filter for Y-data
10
0
0
-10
5 10 15 20 25 30 35 40 45 50 55 60 65 70
-20
-30
-40
-50
-60
Frequency[MHz]
Fig. 46 x2 Over-sampling filter for 1080i/720p
3
2
1
0
-1 ⁰
-2
-3
-4
-5
Aperteu Filter
10
20
30
40
MODE3
MODE2
MODE1
MODE0
Frequency[MHz]
Fig. 45 Aperture Filter
x4 Over-sampling Filter for Cb/Cr
10
0
0
-10
-20
-30
-40
-50
-60
5
10
15 21
26 31 36
Frequency[MHz]
Fig. 47 x4 Over-sampling filter for 1080i/720p
MS0972-E-01
48
2008/12