Explanation Of The Block Diagrams - Sanyo PDG-DXT10L Service Manual

2-7 Explanation of the block diagrams.

2-7-1 Input signal processing
1-1.RGB & Component & DVI input system
The RGB(5BNC) and COMPONENT input signals are led through the multiplexer
circuit. After these signals and DVI signal have been converted into 10-bit digital signals
of RGB each at the A/D converter (U201) incorporated in the VIDEO amplifier, the
resultant signals are output to the scaler (U400).
1-2.Video input system
The VIDEO input and S-VIDEO input signals are decoded into the Y/CbCr (brightness
and chroma) signals at the video decoder (U702). The decoded signals are further
converted into 10-bit digital signals of Y/ CbCr, and then output to the scaler (U400).
2-7-2 Digital video signal processing
2-1.Scaler (U400)
The Y/CbCr signals are processed for picture quality improvement and matrix
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processing at the Scaler circuit, and then converted into the RGB signals.
The RGB and VIDEO input signals are switched over at the selector. After passing
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through the signal adjusting circuit of color space processing, auto-adjustment, etc.,
these signals are written in the RLDRAM.
The video signals called up from the RLDRAM, pass through the definition converter
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circuit, ON-screen display, error diffusion circuit for DLP, V-T compensator circuit, and
such signal processing circuits, and are then output to the optical engine unit (DLP
formatter board).
In the frame memory consisting of the RLDRAM and the FIFO located in the scaler,
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frequency conversion is conducted for the WRITE system and the READ system.
Therefore, the video signals can be output to the optical engine unit (DLP formatter
board) always at the constant timing.
According to the conditions of projector installation, the trapezoidal distortion
•
compensation of the video signals are also effected through the frame memory.
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PDG-DXT10L