msm7661b Oki Semiconductor, msm7661b Datasheet - Page 13

• Manufacturer Part Number: msm7661b
• Description: Ntsc/pal Digital Video Decoder
• Manufacturer: Oki Semiconductor

¡ Semiconductor
7) Parameter for AGC reference level fine adjustment
8) Parameter for sync separation level fine adjustment
The black level is controlled. When the default is specified, the depestal position is output as a
black level (=16).
9) Pedestral clamp selecton
3.
This is a chroma signal processing block.
The following modes can be selected.
1) Use of color bandpass filter
2) ACC loop filter time constant select
3) ACC reference level fine adjustment
4) Parameter for burst level fine adjustment
5) Color killer mode select
6) Parameter for color subcarrier phase fine adjustment
Medium
Fast
Fixed
Pedestral clamp is not used.*
Pedestral clamp is used. (AGC will not operate)
Used*
Not used
Slow
Medium
Fast
Fixed
The threshold level for valid chroma amplitude is selected based on a color burst ratio.
0.5
0.25*
0.125
off
Auto color killer mode*
Forcible color killer
In this block, chroma signals pass through the chroma bandpass filter to cut an unnecessary
band. To maintain a constant chroma level, UV demodulation is performed on these signals
via the ACC correction circuit. (This filter can be bypassed.)
If the demodulation result does not reach a specified level, color killer signals are generated
to fix the ACC gain. This functions as an auto color killer control circuit.
The UV demodulation result is output as chrominance signals via a low pass filter.
Chrominance Block
1/64n*
1/n
0
Factor value 1/1024n
1/64n*
1/n
0
MSM7661B
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