Appendix A Specifications
SCXI-1141/1142/1143 User Manual A-2 ni.com
DC gain error..........................................±0.6% before calibration,
±0.02% after calibration1
DC input offset....................................... mV max
Filter Characteristics
Filter type
SCXI-1141 module..........................8th-order elliptic
SCXI-1142 module..........................8th-order Bessel
SCXI-1143 module..........................8th-order Butterworth
Filter architecture....................................Switched capacitor with prefilters
and postfilters
Rolloff rate..............................................135 dB/octave
Cutoff frequency (fc) range.....................10 Hz to 25 kHz
Cutoff choices (software-selectable)......Divided from 100 kHz or extern al
clock (for example, 25 kHz,
20 kHz, 16.7 kHz, 14.3 kHz,
orfrom external)
Passband ripple
(SCXI-1141 module only)......................0.2 dB, DC to fc
Phase matching
(SCXI-1142 only)...................................3° max error at fc
Stopband attenuation
SCXI-1141module...........................80 dB at 1.5 × fc
SCXI-1142 module..........................80 dB at 6 × fc
SCXI-1143 module..........................80 dB at 3.2 × fc
Prefilter aliasing rejection.......................> 80 dB below 99 × fc
> 40 dB above 99 × fc
Sampled image + clock feedthrough......<–75 dB
1 SCXI-1141/1142/1143 module factory calibration conditions: Vin(–) = 0 V, Vin(+) = ±fullscale
10 9.5
Gain
------------+
⎝⎠
⎛⎞