AK8811 Datasheet, PDF (14/36 Pages) Asahi Kasei Microsystems – NTSC/PAL Digital Video Encoder

ASAHI KASEI
[AK8811/12]
♦ Video Signal Conversion
Video reconstruction module converts the multiplexed data (ITU-R. BT601 Y/Cb/Cr) to the
interlace format of NTSC-M, PAL-M, PAL-B,D,G,H,I,N and other formats (ex. NTSC-4.43 and
PAL60). The video reconstruction format, the line number, the color encode way(NTSC or PAL)
and the frequency of Color Sub-carrier is specified by [Video Process 1 register(01H)]. (cf. Burst
Signal Table) The frequency and the phase of Color Sub-carrier are also adjustable by [Sub C.
Freq. register(06H)] and [Sub C. Phase register(07H)]. The Sub-carrier has a free-running
mode and a reset-mode. In the reset-mode, the Sub-carrier is reset automatically to the initial
phase for every 4 fields (NTSC) or 8 fields (PAL).
♦ Component Video Output
Video output mode is set by VS-bit of [ Video Process 3 register (03H) ].
AK8811/12 can output not only the set of composite video signal and S-video signal but also can
output component video signals(Y/Cb/Cr). The component video signals are complied with EIAJ
guideline 1998/3.
VS-bit = 0 : composite video signal and S-video signal output
VS-bit = 1 : component video signal output
♦ Luminance Filter
Luminance signal passes through the 2x Low Pass filter Fig.1 is the characteristic of
Luminance Filter.
Frequency [MHz]
0.0 1.0 2.0 3.0 4.0 5.0 6.0 7.0 8.0 9.0 10.0 11.0 12.0 13.0
10
0
-10
-20
-30
-40
-50
-60
-70
Fig. 1 Luminance Filter
Rev.1.1
14
2000/01