DDP3310B Datasheet, PDF (18/60 Pages) Micronas – Display and Deflection Processor

DDP 3310B
ADVANCE INFORMATION
2.3.4. Horizontal Phase Adjustment
This section describes a simple way to get a correct
horizontal frame position and clamp window for analog
RGB insertion.
1. For a correct scaler function in panorama/water-
glass mode, the digital input data should be cen-
tered to the active video input signal.
2. The clamping pulse for analog RGB insertion can be
adjusted to the pedestal of the input signal with
POFS2.
3. The horizontal raster position of the analog inserted
RGB1/2 signal can be set to the desired frame posi-
tion with POFS3.
4. The horizontal position of the digital RGB signal can
be shifted to the left and right with NEWLIN. Follow-
ing values allowed in respect to POFS2:
− 90 < (POFS2+NEWLIN) − (Clk×SFIF) < 580
− Clk = 3 @ LLC2 = 27 MHz
− Clk = 2.5 @ LLC2 = 32 MHz
5. Now the positioning of horizontal blanking and the
picture frame generator can be done.
2.3.5. Vertical Synchronization
The number of lines per field can be adjusted by soft-
ware (LPFD). This number is used to calculate the ver-
tical raster. The DDP synchronizes only to a vertical
sync within a programmable detection window (LPFD
± VSYNCWIN). If there is no vsync, the DDP runs with
maximum allowed lines and if the vertical frequency is
to high, it runs with minimum allowed lines. The
smaller the detection window, the slower the DDP gets
synchronized to the incoming vertical sync. In case of
an interlaced input signal, it is possible to display both
fields at the same raster position by setting R_MODE
to 1 or 2.
An automatic field length adaptation can be selected
(VA_MODE). In this case, the vertical raster will be cal-
culated according to the counted number of lines per
field instead from LPFD. This is useful for video
recorder search mode when the number of lines per
field does not comply with the standard, or if you want
to use a common value of LPFD for PAL and NTSC
(e.g.: LPFD = 290; VSYNCWIN = 54).
2.3.6. Vertical and East/West Deflection
The calculations of the Vertical deflection and East/
West correction waveforms are done in the internal
processor. They are described as polynomials in x,
where x varies from −0.5×zoom to +0.5×zoom for one
field. For zoom>1 the range is limited between −0.5
and +0.5.
The vertical deflection waveform is calculated as fol-
lows (without EHT compensation):
V = vpos + ampl ⋅ (x + lin ⋅ x² + scorr ⋅ x³ )
– VPOS
– AMPL
– LIN
– SCORR
defines the vertical raster position
is the vertical raster amplitude (zoom≥1)
is the linearity coefficient
is the coefficient for S-correction
The vertical sawtooth signal will be generated from a
differential current D/A converter and can drive a DC
coupled power stage. In order to get a faster vertical
retrace timing, the output current of the vertical D/A-
converter can be increased during the retrace for a
programmable number of lines (FLYBL). The range
between the end of the flyback and the beginning of
the raster is also programmable (HOLDL).
The East/West deflection waveform, generated from a
single-ended D/A converter, is given with the equation:
E ⁄ W = width + tcorr ⋅ x + cush ⋅ x² + corner ⋅ x⁴
– WIDTH
– TCORR
– CUSH
– CRNU
– CRNL
is a DC value for the picture width
is the trapezoidal correction
is the pincushion correction
is the upper corner correction
is the lower corner correction
-0.5
-0.3
-0.1
0.1
0.3
0.5 x
Fig. 2–15: Vertical and East/West deflection waveforms
18
-0.5
-0.3
-0.1
0.1
0.3
0.5 x
Micronas