Philips EM7U LCOS, Руководство по обслуживанию

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SCALER (Figure 49)
IC 7407 is a highly integrated system on a chip that interfaces the YUV signal from the SSB,
the DVI interface, or the Analog HD inputs to the 1280x720 Light Engine. The Scaler, 7407,
is a 352 Pin Ball Grid array device.
Video Data from the Eagle for the NTSC signal is already scaled correctly in the Eagle. The
inputs from the DVI or 2H Inputs may require some Scaling. This function is performed by
the Scaler. The Scaler can also perform a 1H to 2H conversion allowing NTSC inputs into
AV3 and AV4. However, the Scaler is not as efficient as the Feature Box and Eagle on the
SSB. Therefore, 1H NTSC inputs should be applied only to AV1, AV2, or the Side input for
best results. The Scaler can also display two different inputs in a Split-Screen format. This
can be done between the NTSC inputs or one of the 2H inputs. This is not possible between
two of the 2H inputs. There are two video data inputs to 7407. The YUV input goes to the
Video Port. This is the digital video information from the SSB. AV3, AV4, AV5, and AV6 are
applied to the Graphics Port. Among the inputs that 7407 can process from the Graphics
Port are VGA, SVGA, XGA, and 1080I. The Horizontal Image Scaler, Crisp Image Scaler, and
Spatial Noise Reduction circuits perform part of the scaling functions, create the Spit Screen
if selected by the user, and make picture enhancements. The other Scaler scales the picture
to 1280x720 to meet the requirements of the Light Engine. The Scaler IC has its own internal
memory to store the frames while they are being processed.
The Microprocessor in the Scaler controls the operation of the Scaler and several external
devices. This is a slave Microprocessor of the OTC located on the SSB. The OTC communi-
cates with the Scaler via the PLD IC. Two external memory ICs, 7406 and 7409, store the
program information for the Scaler. The NVM, 7405, stores the settings for the IC. The
Display Port outputs the processed video data on three 8-bit lines, SCR_RED, SCR_GREEN,
and SCR_BLUE.
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SCALER IC