The National Instruments SCXI-1142 Lowpass Filter Input Module (Part Number: 776572-42) is designed for antialiasing applications and general-purpose signal amplification and filtering. Featuring a Bessel filter response across eight input channels, this module is compatible with National Instruments E/M Series data acquisition (DAQ) instruments and operates in both multiplexed and parallel modes. The SCXI-1142 is equipped with 8th-order Bessel filters that preserve signal phase integrity, making it ideal for applications requiring simultaneous sampling. The filters integrate both Software-Controlled Filters (SCFs) and Continuous-Time Filters (CTFs); while SCF technology allows for easy software configuration of the cutoff frequency, the module's hybrid design includes a CTF prefilter to prevent aliasing and a postfilter to accurately reconstruct the sampled waveform.

For enhanced precision, the SCXI-1142 incorporates calibration hardware to eliminate error sources. Its software-programmable analog switches can ground the inputs of instrumentation amplifiers, facilitating offset error calibration through automatic input zeroing. Users can utilize an external reference voltage for tailored calibration to their specific operating conditions. The module also includes DC compensation circuits, ensuring high DC accuracy regardless of whether lowpass filtering is engaged. Calibration constants are securely stored in onboard EEPROM, enabling the NI-DAQ system to automatically apply corrections for gain errors. While the SCXI-1142 has been designated as obsolete by National Instruments, it remains available for purchase and repair through Apex Waves.

The module has an input and output range of ±5 V, with DC input coupling and dimensions of 1.2 by 6.8 by 8.0 inches. It is backed by a warranty of 2-3 years, and both user and maintenance manuals are available for download. For pricing information, please contact a sales representative.