cxa3522r Sony Electronics, cxa3522r Datasheet - Page 27

• Manufacturer Part Number: cxa3522r
• Description: Driver/timing Generator For Color Lcd Panels
• Manufacturer: Sony Electronics

6) TG block
• PLL and AFC circuits
• H-Position
• Right/left (RGT) and/or up/down inversion (DWN)
• Overscan display mode
• AC driving of LCD panels during no signal
This adjusts the horizontal display position. Set this function so that the picture center matches the center of
the LCD panel.
The video display direction can be switched. The horizontal direction can be switched between right scan and
left scan, and the vertical direction between down scan and up scan. Set the display direction in accordance
with the LCD panel mounting position.
Displaying black in the up/down 6 lines and right/left 18 (19) dots of the display area generates overscan
area (black frame) in the display area.
The output signal runs freely so that the LCD panel is AC driven even when there is no sync signal from the
FIL IN (Pin 69) pin or from the CSYNC/HD (Pin 5) and VD (Pin 10) pins. It also runs freely when there is no
sync signal during 281H (NTSC) and 331H (PAL) of display system. Respective cycles are 281H (NTSC) and
331H (PAL).
A PLL circuit can be comprised by connecting a PLL circuit phase comparator and frequency division counter
and external VCO and LPF circuits.
The PLL error detection signal is generated using the phase comparison output of the entire bottom of the
horizontal sync signal and the internal frequency division counter as the RPD output. RPD output is
converted to DC error voltage with the lag-lead filter, and then it changes the capacitance of the varicap
diode to stabilize the oscillation frequency.
The PLL of this system is adjusted by setting the reverse bias voltage of the varicap diode so that the point at
which RPD changes is at the center of the horizontal sync signal window as shown in the figure below.
Horizontal sync signal
240 LINES
RPD (Pin 24)
Normal display
Display area
490 DOTS
WL
WS
WH
– 27 –
Black frame display
Display area
453 DOTS
WL
WS
WH
Black display
6 LINES
228 LINES
6 LINES
WL = WH
CXA3522R