National Instruments SCXI-1141

The National Instruments SCXI-1141 Lowpass Filter Input Module (Part Number: 776572-41) is designed for sophisticated lowpass filtering and antialiasing requirements, featuring eight differential-input amplifiers paired with lowpass elliptic filters. Suitable for general-purpose signal amplification and filtering, this module exhibits sharp filter roll-off, allowing all eight channels to be set to the same cut-off frequency. It also includes the capability to programmatically bypass the lowpass filter on a per-channel basis. With a maximum sampling rate of 333 kS/s and an attenuation rate of 135 dB/octave, the SCXI-1141 can be utilized in conjunction with National Instruments E/M Series DAQ instruments, enabling multiple modules to be controlled by a single DAQ device within a chassis.

For seamless integration, the SCXI-1304 and SCXI-1305 Shielded Terminal Blocks are recommended, featuring screw terminals for easy signal connections and all necessary circuitry for both AC and DC coupling, as well as floating or ground-referenced signals. The SCXI-1141 supports analog and switched capacitor filters, offering the flexibility of 10,000 discrete software-programmable cut-off frequencies while maintaining the low-noise performance typical of conventional time-active filters. An external clock input and output facilitate user-defined cut-off frequencies in tracking filter applications. Activating the Auto-zero mode enhances measurement precision by grounding the inputs internally and effectively compensating for offset in subsequent measurements.

The SCXI-1141 is compatible with the NI-DAQmx driver software, enabling operation with various software environments such as LabVIEW and LabWindows/CVI; configuration is easily accomplished via the Measurement & Automation Explorer (MAX) tool. The module measures 1.2 x 6.8 x 8.0 inches. Although classified as obsolete, the SCXI-1141 remains available for purchase and repair through Apex Waves.