National Instruments PXI-4462 PXI Sound and Vibration Module

National Instruments created the PXI-4462 (Part Numbers: 779132-01, 779688-01, 779131-01), a high-performance 4-input sound and vibration module, for precise measurements in sound and vibration applications. With its delta-sigma design and 24-bit resolution ADC, it offers remarkable precision and dynamic range. It enables high-fidelity signal capture with sample rates ranging from 1 kS/s to 204.8 kS/s in increments as tiny as 181.9 μS/s. The difference between the part numbers of the sound and vibration module is that part number 779131-01 is the standard version of the device, while part number 779688-01 is hybrid slot compatible. Part number 779132-01 is equipped with a sound and vibration measurement suite. 

This module offers four independently selected software sampled input channels that can be configured as differential or pseudodifferential. Input coupling can be set to AC or DC on a per-channel basis, offering flexibility for various measurement scenarios. In order to accommodate varying input signal levels, the PXI-4462 has a programmable gain amplifier stage that allows gain adjustment from -20 to +30 dB in 10 dB steps. Because it supports single-ended and differential signal connections, it can be used with a variety of transducers.

The PXI-4462 has the ability to synchronize data acquisition with external events using analog and digital triggering capabilities. Any input channel can provide analog triggers, which have hysteresis, slopes, and trigger levels that can be adjusted. Digital triggers with adjustable polarity and minimum pulse width provide additional synchronization possibilities and are compatible with 5V TTL logic.

The module uses both analog and digital filters to eliminate aliasing and guarantee accurate frequency-domain readings. With a mean total harmonic distortion (THD) of -107 dB, the analog inputs provide good amplitude flatness of ±0.1 dB between DC and 92 kHz.

The PXI-4462 is appropriate for a number of applications, including audio testing, automotive noise, vibration, and harshness (NVH), and machine condition monitoring. Its features include software-configurable AC/DC coupling and IEPE conditioning. Precision measurements using microphones, accelerometers, and other transducers—even with wide dynamic ranges—are made possible by its hardware and software support. Efficient data handling for real-time applications is ensured by its FIFO buffer size of 2,047 samples and direct memory access (DMA) for data transfer.