ADV7189KST Analog Devices Inc, ADV7189KST Datasheet - Page 29

• Manufacturer Part Number: ADV7189KST
• Description: IC VIDEO DECODER NTSC 80-LQFP
• Manufacturer: Analog Devices Inc
• Type: Video Decoderr

Specifications of ADV7189KST

• Applications: Set-Top Boxes, Video Players, Recorders
• Voltage - Supply, Analog: 3.15 V ~ 3.45 V
• Voltage - Supply, Digital: 1.65 V ~ 2 V
• Mounting Type: Surface Mount
• Package / Case: 80-LQFP
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant

The luma shaping filter has three control registers:
•
•
•
In automatic mode, the system preserves the maximum possible
bandwidth for good CVBS sources (since they can successfully
be combed) as well as for luma components of YPrPb and YC
sources, since they need not be combed. For poor quality
signals, the system selects from a set of proprietary shaping
filter responses that complements comb filter operation in order
to reduce visual artifacts.
The decisions of the control logic are shown in Figure 11.
YSFM[4:0] allows the user to manually select a shaping
filter mode (applied to all video signals) or to enable an
automatic selection (depending on video quality and video
standard).
WYSFMOVR allows the user to manually override the
WYSFM decision.
WYSFM[4:0] allows the user to select a different shaping
filter mode for good quality CVBS, component (YPrPb),
and S-VHS (YC) input signals.
COMPLEMENT COMB
AUTO SELECT LUMA
SHAPING FILTER TO
BAD
SELECT WIDEBAND
FILTER AS PER
WYSFM[4:0]
QUALITY
VIDEO
Figure 11. YSFM and WYSFM Control Flowchart
1
YES
Rev. B | Page 29 of 104
WYSFMOVR
GOOD
YSFM IN AUTO MODE?
00000 OR 00001
SET YSFM
SELECT AUTOMATIC
WIDEBAND FILTER
YSFM[4:0] Y Shaping Filter Mode, Address 0x17 [4:0]
The Y shaping filter mode bits allow the user to select from a
wide range of low-pass and notch filters. When switched in
automatic mode, the filter is selected based on other register
selections, for example, detected video standard, as well as
properties extracted from the incoming video itself, for
example, quality, time base stability. The automatic selection
always picks the widest possible bandwidth for the video input
encountered.
•
•
WYSFMOVR Wideband Y Shaping Filter Override,
Address 0x18 [7]
Setting the WYSFMOVR bit enables the use of the WYSFM[4:0]
settings for good quality video signals. For more information,
refer to the general discussion of the luma shaping filters in the
Y Shaping Filter section and the flowchart shown in Figure 11.
Table 59.
WYSFMOVR
0
1 (default)
If the YSFM settings specify a filter (that is, YSFM is set to
values other than 00000 or 00001), the chosen filter is
applied to all video, regardless of its quality.
In automatic selection mode, the notch filters are only used
for bad quality video signals. For all other video signals,
wide band filters are used.
0
FILTER REGARDLESS FOR
GOOD AND BAD VIDEO
USE YSFM SELECTED
NO
Description
Automatic selection of shaping filter for good
quality video signals.
Enable manual override via WYSFM[4:0].
ADV7189