msm7664 Oki Semiconductor, msm7664 Datasheet - Page 20

• Manufacturer Part Number: msm7664
• Description: Ntsc/pal Digital Video Decoder
• Manufacturer: Oki Semiconductor

¡ Semiconductor
7) AGC loop filter time constant selection (related register AGCLF[7:6])
8) Parameter for fine adjustment of AGC sync depth (related register AGCLF[5:0])
9) Parameter for fine adjustment of sync removal level (related register SSEPL[6:0])
10)Pedestal clamp selection (related register SSEPL[7])
3. Chrominance Block
This block processes the chroma signals.
The following operating modes can be selected.
1) Selection of chroma bandpass filter usage (related register CHRC[2])
2) ACC loop filter time constant selection (related register ACCLF[6:5])
3) ACC reference level fine adjustment (related register ACCLF[4:0])
4) Parameter for burst level fine adjustment (related register CHRC[1:0])
5) Color killer mode selection (related register MRB[5])
6) Parameter for fine adjustment of color subcarrier phase (related register HUE[7:0])
These are designed times from the input gain being rapidly lowered to 50% (–6 dB) of the
value at a stable state when normal signals are input till the output being returned to –1 dB
(actually these times differ depending on the signal state).
MGC mode: manual gain setting is possible by register AGCLF[5:0]
AGC reference level is changed.
The black level is adjusted. The default setting outputs the pedestal position as a black level
(=16).
Do not use pedestal clamp*
Use pedestal clamp (at this time, AGC does not operate, MGC operates)
These are designed times from the input gain being rapidly lowered to 50% (–6 dB) of the
value at a stable state when normal signals are input till the output being returned to –1 dB
(actually these times differ depending on the signal state).
MCC mode: manual gain setting is possible by register ACCLF[4:0]
ACC reference level is changed.
Threshold level at which chroma amplitude becomes valid is selected based upon color burst
ratio.
Off: The color killer function is turned off. If decoloration occurs while decoding a still picture,
setting the threshold level to "off" will reduce the decoloration.
HUE control function
Slow
Medium
Fast
MGC mode
Do not use*
Use
Fast2
Medium
Fast
MCC mode
0.5
0.25*
0.125
Off
Auto color killer mode*
Forced color killer
Set the SSEPL[7] value to a 0 when the MGC mode is used.
convergence time
convergence time
903 ms
225 ms*
56 ms
0
27 ms
424 ms*
106 ms
0
PEDL7664-01
MSM7664
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