Stanford Research Systems SIM954 Operation And Service Manual page 23

2.5 Isolation
SIM954 300 MHz Dual Inverting Driver Amplifier
ingly worse at higher frequencies, while with the amplifier o it gets
increasingly better. At the highest frquency (500 MHz), well above
the amplifier's bandwidth, both curves converge to roughly the same
value, which is essentially a measure of the parasitic impedances of
the amplifier's feedback path.
Figure 2.6: SIM954 output to input isolation. The dashed line repre-
sents power-o isolation, the solid line represents the powered state.
The curves are interpolated between measured data (dots).
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