DATA SHEET
VSP 94x2A
Table 2–6: Configurations of input signals
Mode
CLMPVG
CLMPVRB GOFST
RBOFST
DCLMPF
YUV, sync on Y
YUV, sync on H,V
RGB, sync on G
RGB, sync on RGB
RGB, sync on H,V
80
16
80
80
16
128
128
16
64
0
128
128
0
Don’t care
0 (clamping enabled)
Don’t care
64
64
0
80
64
0
Don’t care
16
0 (clamping enabled)
1 (clamping disabled)
1 (clamping disabled)
RGB with fast-blank, synchron to CVBS 16
16
0
0
YUV with fast-blank, synchron to CVBS
16
128
0
128
2.2.3. Clamping
RGB-prefiltering
10
0
When using the dynamic softmix-mode with fast-blank,
clamping of fast-blank input must be disabled by
DCLMPF. The analog clamping value of red and blue
input (V and U resp.) can be adjusted by CLMPVRB.
The analog clamping value of green input (Y resp.) can
be adjusted by CLMPVG. Depending on the input sig-
nal format (YUV, RGB, sync signal or not) these bits
must be set accordingly. On the digital side, a correc-
tion of the analog clamping value must be performed
to reconstruct the blacklevel. This is achieved by RBO-
FST and GOFST. (see Table 2–6 on page 15)
3
10
20
30
40
0
5
10
Frequency [MHz]
15
20
2.2.4. Digital Prefiltering
Fig. 2–18: Digital Prefiltering of RGB Input
2.2.5. RGB → YUV Matrix
A digital prefiltering can be enabled. A band limitation
is required, because the following deskewing filter per-
forms best at frequencies of below 14 MHz. The filter-
ing is performed in all four channels and can be dis-
abled by AABYP. For signal conversion to 4:2:2, an
additional chrominance lowpass can be enabled by
CHRSF. The deskewing filter can be disabled by
SKEWSEL. This is necessary when using the H50-pin
in connection with a Micronas picture-in-picture device
(e.g. SDA 938x, SDA 948x, SDA 958x). In this applica-
tion, the RGB input (in1, in2, in3) of the PiP can not be
used for other RGB/YUV signals (e.g. ‘SCART’ is not
possible). As there is a pixel skew on H50, this pin is
NOT suited to synchronize any IC, except for the
above mentioned PiP ICs
RGB or YUV signals are selected by YUVSEL. The
matrix coefficients are set according to ITU recommen-
dations.
Y
U
V
R
G
B
0,299 0,587 0,114
–0,147 –0,289 0,436
0,615 –0,515 –0,100
=
⋅
Fig. 2–19: RGB to YUV Matrix
Micronas
Aug. 16, 2004; 6251-552-1DS
15
MICRONAS [ MICRONAS ]
