ML6420
USING VIDEO FILTERS (CONTINUIED)
The output waveform is not symmetric. All ringing occurs
after the main pulse. Result is visual smearing and fine
ghosting to the right of every edge in the picture. See old
Figure 19a.
Analog Filtering in the Time Domain
Output waveform is symmetric. Ringing is about the same
as ML6420 alone. Difference between purely analog and
analog/digital approach is subtle and will only have a
material effect on multi-pass video processing.
Phase Corrected Analog Filter
Output waveform is substantially symmetric. Ringing is
greatly reduced. Result is increase in apparent resolution.
No smearing or ghosting.
TYPICAL ANALOG FILTER
Figure 19a.
ML6420
5.5MHz TYP
Figure 19b.
DIGITAL FILTER
HALF-BAND
Figure 19c.
10
MICRO-LINEAR [ MICRO LINEAR CORPORATION ]
