National Instruments SCC-PWR02, User Manual

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SCC-LP Series Lowpass Filter Modules User Guide 14 ni.com
The horizontal axes of the first two plots are normalized to the SCC-LP XX
cutoff frequency. When the input frequency (f) equals the cutoff frequency
(fc), the normalized frequency has a value of 1.
The vertical axis of the third plot is normalized to the magnitude of the step
input voltage. When the step-response output voltage equals the magnitude
of the step-input voltage, the normalized step response is 1 V
OUT
/V
IN
.
Figure 6a shows that the SCC-LP XX provides 80 dB attenuation above
ten times the cutoff frequency. Figure 6b shows variation in the group
delay of the SCC-LP
XX . Figure 6c shows the SCC-LP XX response to a
step input. As shown, the peak voltage of the output is greater than the
magnitude of the step input. If you expect step inputs, choose a gain setting
and input range on the E Series DAQ device that allow for the effects of
ringing. Otherwise the DAQ device input may be saturated, resulting in
invalid data.