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SCC-LP Series Lowpass Filter Modules User Guide

14

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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.

Содержание SCC-PWR02

Страница 1: ...SCC PWR02...

Страница 2: ...conventions are used in this guide Angle brackets that contain numbers separated by an ellipsis represent a range of values associated with a bit or signal name for example P0 3 0 The symbol leads you...

Страница 3: ...an introduction to a key concept This font also denotes text that is a placeholder for a word or value that you must supply monospace Text in this font denotes text or characters that you should enter...

Страница 4: ...ules User Guide SC 2345 2350 User Manual available at ni com SCC Quick Start Guide available at ni com Read Me First Safety and Radio Frequency Interference SC 2345 Quick Reference Label 68 pin E Seri...

Страница 5: ...ibed in the Connecting the Input Signals section The SCC LPXX can function as either the first or the second stage of a dual stage configuration Plug the first stage SCC into any socket J X 9 and plug...

Страница 6: ...signal sources in high noise environments connect the negative terminal of the signal source to the AI GND terminal on the SC 2345 screw terminal block to reduce common mode noise Figure 1 SCC LPXX S...

Страница 7: ...HX 2 Calculate the SCC LPXX voltage using this formula VLP 2VESERIES where VLP is the SCC LPXX input voltage VESERIES is the E Series DAQ device input voltage Specifications These ratings are typical...

Страница 8: ...rate 80 dB decade 3 dB cutoff frequency fc SCC LP01 25 Hz SCC LP02 50 Hz SCC LP03 150 Hz SCC LP04 1 kHz Passband ripple System Noise Total harmonic distortion THD at fc 90 dB Wide band noise DC to 1 M...

Страница 9: ...V 15 8 mA max Digital power 0 0 mW max Physical Dimensions 8 89 cm 2 92 cm 1 85 cm 3 50 in 1 15 in 0 73 in Mass 37 g 1 3 oz I O connectors One 20 pin right angle male connector one 4 pin screw termin...

Страница 10: ...romagnetic Compatibility Emissions EN 55011 Class A at 10 m FCC Part 15A above 1 GHz Immunity EN 61326 1997 A2 2001 Table 1 CE C Tick and FCC Part 15 Class A Compliant Note For full EMC compliance ope...

Страница 11: ...lay is not constant and the step response exhibits a moderate amount of overshoot ringing These characteristics present no problems in applications where only the amplitude of signal frequency compone...

Страница 12: ...Modules User Guide Figure 3 Typical SCC LP02 Response Curve Figure 4 Typical SCC LP03 Response Curve Frequency Hz Amplitude dB 25 0 1 2 3 4 5 10 20 25 50 100 20 0 15 0 10 0 5 0 0 0 Frequency Hz Ampli...

Страница 13: ...SCC LP Series Lowpass Filter Modules User Guide 12 ni com Figure 5 Typical SCC LP04 Response Curve 1 2 3 4 5 10 20 50 1000 2000 25 0 20 0 15 0 10 0 5 0 0 0 2 5 Frequency Hz Amplitude dB...

Страница 14: ...cteristics of the SCC LPXX Figure 6 Theoretical Transfer Characteristics a Frequency Response 0 0 10 15 0 5 Normalized Frequency f fc Amplitude dB 1 1 5 5 10 20 40 60 80 100 b Group Delay 2 0 1 0 15 0...

Страница 15: ...the magnitude of the step input voltage the normalized step response is 1 VOUT VIN Figure 6a shows that the SCC LPXX provides 80 dB attenuation above ten times the cutoff frequency Figure 6b shows var...

Страница 16: ...rate is known as the Nyquist frequency To prevent aliasing you must remove all of the signal components with frequencies greater than the Nyquist frequency from an input signal before you sample it Wh...

Страница 17: ...6 Input 0 VDC to the SCC LPXX 7 Have the E Series DAQ device read the channel again and record the new value 8 Calculate the difference between the two values you recorded first reading second reading...

Страница 18: ...17 SCC LP Series Lowpass Filter Modules User Guide SCC LPXX Module Pin Assignments Figure 8 shows the I O connector pins on the bottom of the module Figure 8 SCC Module Bottom View 1 Pin 1 2 Pin 2 3 P...

Страница 19: ...X and AI X 8 are the analog input signal channels of the E Series DAQ device AI GND is the analog input ground signal and is the reference for AI X and AI X 8 A GND is the reference for the 15 V suppl...

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