Hitachi 46W500 Training page 27

DP-3X MICROPROCESSOR DATA COMMUNICATIONS CIRCUIT EXPLANATION
I501 Rainforest (Video/Chroma Processor)
The Video Processing IC (Rainforest) is responsible for controlling video/chroma processing before the signal is
made available to the CRTs. Some of the emphasis circuits are controlled by the customer's menu. As well as
some of them being controlled by AI, (Artificial Intelligence).
Communication from the Microprocessor I001 via pins (31 SDA2 and 28 SCL2) to the Rainforest IC pins (28
and 30) respectively.
IA01 BBE Audio Control (Surround)
This chassis utilizes BBE Surround.
Communication from the Microprocessor via pins (31 SDA2 and 28 SCL2) to the Audio Control IC pins (13 and
14) respectively.
ON THE TERMINAL PWB: (Through the connector PST2)
IY01 3D Y/C (IC mounted directly on the Terminal PWB).
The 3D Y/C IC is a Luminance/Chrominance separator, as well as a 3D adder. Separation takes place digitally.
Using advanced separation technology, this circuit separates using multiple lines and doesn't produce dot pattern
interference or dot crawl. The 3D effect is a process of adding additional emphasis signals to the Luminance and
Chrominance. These signals relate specifically to transitions. Transitions are the point where the signal goes from
dark to light or vice versa. The 3D adds a little more black before the transition goes to white and a little more
white just before it gets to white. It also adds a little more white just before it goes dark and a little more dark just
before it arrives. This gives the impression that the signal pops out of the screen or a 3D effect.
The Microprocessor communicates with the 3D Y/C IC via I
from the Microprocessor are pins (40 SDA3 and 39 SCL3) to connector PST2 pins (17 and 16) to the 3D Y/C
IY01 pins (47 and 46) respectively.
The Microprocessor also is able to turn on and off circuits within the 3D Y/C circuit determined by customer
menu set-up.
IV01 A/V Selector
The A/V Selector IC is responsible for selecting the input source for the Main Picture as well as the source for
the PinP or Sub picture. Communication from the Microprocessor via pins (30 SDA1 and 29 SCL1) to the PST2
connector pins (13 and 12) respectively then to IV01 pins (34 and 33) respectively.
IV11 DAC (Digital to Analog Converter)
This IC works controlling different switches via the DAC0, DAC1 and DAC2 control lines.
•
DAC0 pin 7 controls the V. Sync selector IV07 for DVI 1/2 input via pin 9 and H Sync selector
IV06 DVI 1/2 via pin 9.
•
DAC1 pin 6 controls the Y selector IV07 for DVI 1/2 input via pin 10 and Y selector IV06 for the
Media Card via pin 10.
•
DAC2 pin 5 controls the V. Sync selector IV07 for DVI 1/2/Media Card input via pin 11 and V.
Sync selector IV06 for the DVI 1/2/Media Card via pin 11.
Communication from the Microprocessor via pins (31 SDA2 and 28 SCL2) to connector PST2 pins (15 and 14)
to IV11 pins (14 and 15) respectively.
IV03 Main/PinP Y Pr/Pb Selector
Any input that is in the Y Pr/Pb or Y Cr/Cb state, will have be selected by this IC. Both for the Main Picture and
the PinP (Sub) picture.
The Main/PinP Y Pr/Pb Selector IC selects the appropriate input between Components 1 or 2, DVI 1 or 2, ATSC
Tuner and/or DVD Player, if provided. Communication from the Microprocessor via pins (31 SDA2 and 28
SCL2) to connector PST2 pins (15 and 14) to IV03 pins (26 and 27) respectively.
2
C bus data and clock. The communications ports
(Continued on page 4)
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