Datasheet
Application Information (Continued)
It is very important to keep the lead lengths to a minimum
and to provide a low impedance current path by using a
ground-plane on the board.
Caution: If R
L
is removed, the current balance at the output
of LM7121 would be disturbed and it would have to supply
the full amount of load current. This might damage the part if
power dissipation limit is exceeded.
Color Video on Twisted Pairs Using Single Supply
The circuit shown in
Figure 4
can be used to drive in excess
of 25 meters length of twisted pair cable with no loss of reso-
lution or picture definition when driving a NTSC monitor at
the load end.
DS012348-93
FIGURE 3. Waveform across a 100Ω Load
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