Datasheet
Application Information (Continued)
Differential Gain and Differential Phase errors measured at
the load are less than 1
%
and 1˚ respectively.
R
G
and C
C
can be adjusted for various cable lengths to com-
pensate for the line losses and for proper response at the
output. Values shown correspond to a twisted pair cable
length of 25 meters with about 3 turns/inch (see
Figure 5
for
step response).
The supply voltage can vary from 8.5V up to 30V with the
output rise and fall times under 12 ns. With the component
values shown, the overall gain from the input to the output is
about 1.
Even though the transmission line is not terminated in its
nominal characteristic impedance of about 600Ω, the result-
ing reflection at the load is only about 5
%
of the total signal
and in most cases can be neglected. Using 75Ω termination
instead, has the advantage of operating at a low impedance
and results in a higher realizable bandwidth and signal
fidelity.
DS012348-94
Note:
Pin numbers shown are for SO-8 package.
*
Input termination of NTSC monitor.
FIGURE 4. Single Supply Differential Twister Pair Cable Transmitter/Receiver
8.5V ≤ V
CC
≤ 30V
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