Circuit Description; Main Board - Sony VPL-EX100 Service Manual

3-2. Circuit Description

3-2-1. Main Board

Video input block
Composite video and S video signals are input from VIDEO and S VIDEO of S VIDEO IN/VIDEO IN.
The two input signals are directly input to a video processor and converted into digital data using the
internal AD converter of the video processor.
PC input block
*
The input signals from RGB of two channels INPUT A and INPUT B are input to a video processor. One
of the two signals is selected using a switching menu and converted into digital data using the internal AD
converter of the video processor. The signal selected using a video buffer is output from MONITOR of
OUTPUT.
A component signal and video GBR signal as well as a PC signal can be also input to the RGB/Y P P
B R
connector of INPUT A.
Only a PC signal can be input to the RGB connector of INPUT B.
AUDIO input block
*
A signal is input from the L (MONO) AUDIO R of S VIDEO IN/VIDEO IN and AUDIO of INPUT A/B
stereo mini jacks. The signal selected using an audio processor is output to AUDIO of OUTPUT and a
speaker.
MONITOR output block
*
An RGB signal is input from INPUT A/B , and the channel signal selected by input switching is output
from MONITOR of OUTPUT. The channel signal is not output when VIDEO and S VIDEO are selected.
*
The signal input from AUDIO of INPUT A/B is output from AUDIO of OUTPUT. The output signal can
be changed using a volume control.
The signal output from an internal speaker is switched by setting a speaker menu to ON and OFF.
Video processor & system control block
PW-950 made by Plxelworks is installed in main CPU, and an R5P series made by Renesas is installed in
sub-CPU. Input signal's pixel count conversion, aspect conversion, and OSD addition are performed using
these ICs. These ICs also enable brightness, sharpness, chroma, hue, and system controls.
Control target: Control panel, OSD display, lamp cover switch, LED, and serial control
LCD timing generator (DSD2) block
Using a Sony LCD panel IC, the LCD timing generator block generates a timing pulse that drives an LCD
panel. This block also uses a system in which the driving direction is reversed for each frame. White
balance adjustment, gamma adjustment, and color smudge adjustment as well as timing pulse generation
are performed in this IC.
LCD driver block
The LCD driver block uses a Sony LCD panel drive IC. The LCD panel is 12-phase- driven using the tim-
ing pulse generated using a timing generator. This block mounts GBR and a three-channel circuit.
3-5 (E)
VPL-EX100