TMC22x5yA
PRODUCT SPECIFICATION
If either of the error signals indicates that the magnitude
difference is above the programmed threshold, or if ANEN is
LOW, the adaptive notch filter is bypassed. The output of the
adaptive notch filter is rounded to 8 or 10 bits, or the luma
data that bypasses the coring filter is truncated to 8 or 10 bits
depending upon the CORO register bit.
Programmable U Scalar
The U scalar (UGx) provides the weighting required to
produce (B-Y) or C from the demodulated U signal.
B
hence
(B-Y) = UGx * U
0
-10
-20
where UGx = gain / 0.493, and
C
= UGx * U
B
Adaptive Notch
Filter 1
Adaptive Notch
Filter 32
-30
-40
-50
-60
-70
where UGx = (gain * 448) / Umax
UGx has a scaling range of 0 to (2047/256).
Programmable V Scalar
Adaptive Notch
Filter 2
The V scalar (VGx) provides the weighting required to
produce (R-Y) or C from the demodulated V signal.
R
Normalized Frequency
hence
(R-Y) = VGx * V
Figure 25. Adaptive Notch Filters
where VGx = gain / 0.877, and
Luma Notch Filter
C
= VGx * V
R
The simple luma notch filter is centered at 0.25 of normal-
ized frequency, it therefore intended for use only in the sub-
carrier mode (4 * fSC) and for limited use with 13.5MHz
NTSC as the subcarrier sits at 0.265 of normalized fre-
quency. The notch filter is enabled by setting the NOTCH
register bit HIGH.
where VGx = (gain * 448) / Vmax
VGx has a scaling range of 0 to (1023/256).
ProgrammableY Scalar
The Y scalar (YGx) provides the scaling for the luminance
0
-10
-20
-30
-40
-50
-60
-70
signal if the output is YC C , or controls the magnitude of
B R
the RGB output along with the U scalar and V scalar. It is not
possible to control the magnitude of the RGB signals inde-
pendently.
YGx has a scaling range of 0 to (1023/256).
Programmable MS Scalar
The sync scalar (SGx) provides the scaling for the sync
signal if the output requires sync on RGB. The programmed
sync scaling factor is used during the horizontal and vertical
burst blanking periods. During the active lines, the luma
scaling factor is used to allow scaling of “super blacks” etc.,
which will be passed down the mixed sync path because they
fall below the clamp level.
Normalized Frequency
Figure 26. Luminance Notch Filter
Matrix
SGx has a scaling range of 0 to (1023/256).
The magnitude of the decoded luminance and color differ-
ence signals will vary, not only with the standard, but also
with the input mode. For this reason the output matrix
contains programmable multipliers, and not just fixed
scaling factors. The following sub sections explain the differ-
ent scalar in the output matrix. The gain term in theY, mixed
sync, U and V scalar is the same - only the weighting makes
them different. The scalar are capable of independently
providing 6dB of gain if required.
Fixed (B-Y) and (R-Y) Scalars
These two scalars are zero when the output is YC C and
B R
provide the (B-Y) and (R-Y) weighting when the output is
RGB. These are fixed scaling factors and are derived from
the following equations.
(G-Y) = - [(0.299/0.587) * (R-Y)]
- [(0.114/0.587) * (B-Y)]
or
(G-Y) = - [(1043/2048) * (R-Y)]
- [(398/2048) * (B-Y)]
56
REV. 1.0.0 2/4/03
CADEKA [ CADEKA MICROCIRCUITS LLC. ]
