Mitsubishi DPLUS 74SB -BKA Service Manual page 116

Composite Sync Signal Separator
Composite sync signal separator extract Vsync signal from HIN or SOGIN input pin by filtering pulses
which is less than 6us. The output Vsync signal will be widened about 5.5~6.5us. The output Hsync will
be replaced by 2us pulse during Vsync pulse.
The composite sync signal separator can handle H+V and H exclusive OR V signals. Fig. 5 shows the
timig relationship of the extracted H and V sync signals.
If Hsync output do not want to insert pseudo H pulses (EXTRHS signal) during Vsync pulse, set BY-
PASS bit can let HOUT pin output waveform same as Hsync input (Note: polarity can be controlled by
HOPOL bit).
Fig.6 Timing relationship of composite sync signal separator
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