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6.6 Detail Introduction of PDP circuit boards
6.6.1 VIF Board:
a. Summary:
General digital video signals include Vsync
、
Hsync
、
R(8Bit)
、
G(8Bit)
、
B(8Bit) and Data
Enable (Blank);the VIF of PDP is making for processing these digital signal.
Because PDP belonging a high end product , so its application should include the
functions of Monitor (analog VGA , digital DVI signal input). And for consumer’s
sake , the VIF should have the functions of video , like audio , composite , s-video ,
component signal processing.
Below is the explanation of VIF system:
b. The role of VIF
:
Currently the video signal sources are video cassette recorder , DVD player , CATV ,
RF tuner , VGA card(PC). In order that all the video signal sources can be displayed
on PDP , so we need a interface to transfer these signals to a specified signals for
PDP to display , and this is the function of VIF(Video Interface).
c. Basic framework of VIF board
For dealing with the signals of CVBS, S-video and Component, it requires a video
decoder IC. And the output of video decoder will input to a de-interlace chip IC for a
stable image quality. Because the TV system uses interlace scanning, it causes
flickers on the screen . To improve this situation so we use a de-interlace chip IC.
The ADC(Analog to Digital Converter) IC converts the analog RGB signal to digital
RGB signal. The TMDS(Transition Minimized Differential Signaling) decoder IC
transmits digital RGB signal. All the output of ICs’ signal send to scalar IC. The
relationship is shown as below, and make a brief explanation of the system.
9
Introduction of PDP Circiut
UHF/VHF TV
Cable TV
HDTV
VTR
DVD Player
PC
Home Video
Game
VIF
DIF