Video Signal Flow - Philips L05HD Training Manual

Video Signal flow overview (Figure 8)
There are two sections in the set for processing video. The 1fH section using the Hercules
processes NTSC signals.
The Tuner is controlled by the microprocessor in the Hercules. IF from the Tuner is fed to the
Hercules chip for detection and demodulation. AV1, AV2, Side, and 1fH Component video is
also fed to the Hercules, IC 7200. If an NTSC signal is selected by the Remote or Keyboard,
the selected CVBS (Composite Video) is output on two lines. One CVBS line goes to the
Trident chip, IC 7201, located on the HD panel. CVBS_TXT is fed to IC 7206 on the HD
panel which detects Closed Caption text or teletext. This IC also generates the OSD (On
Screen Display).
If the signal applied to the set is a 2fH signal or better, it is applied to either the YpbPr
Component input or the HDMI input. These signals are fed to a selector switch located on
the HD panel, IC 7205. The selected component or RGB signal if fed to the A/D converter, IC
7210. This signal is fed to the Trident IC 7201 which enhances the picture and scales it to
1080i. Analog RGB out from the Trident IC is fed to the Display Processor, IC 7221, which
performs the picture control functions and inserts the OSD. The output of 7221 is fed to the
CRT panel.
The option settings for the Source selection can be found in Option settings in the SAM
mode.
FIGURE 8 - VIDEO SIGNAL FLOW BLOCK
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