The NI PXI-4462 is a four-channel Dynamic Signal Analyzer delivering simultaneous, high-precision measurement across audio, acoustic, and vibration applications. With 24-bit resolution, sampling rates to 204.8 kS/s, and a 118 dB dynamic range, it captures transient phenomena and spectral content with exceptional fidelity. The module supports programmable gain from -20 dB to +30 dB, input ranges from ±0.316 Vpk to ±42.4 Vpk, and achieves typical THD of -107 dB and spectral noise density of 8 nV/√Hz at 30 dB gain.
Technical Specifications
Analog Inputs
• Four simultaneously sampled channels with 24-bit resolution
• Sampling rates: 204.8 kS/s maximum; minimum increments to 181.9 µS/s; software-programmable standard audio rates (44.1 kS/s, 48.0 kS/s, 96.0 kS/s, 192 kS/s)
• Differential or pseudodifferential configuration (50 Ω between negative input and chassis ground for pseudodifferential)
• AC or DC coupling, independently selectable per channel
• Input voltage ranges: ±0.316 Vpk to ±42.4 Vpk (six programmable gain settings)
• Input impedance: 1 MΩ in parallel with 70 pF (differential)
• Overvoltage protection: ±42.4 Vpk differential; common-mode range ±4.0 V
Dynamic Characteristics
• Dynamic range: 118 dB
• Total harmonic distortion: Typically -107 dB, up to -109 dB
• Amplitude flatness: ±0.1 dB from DC to 92 kHz
• Spurious-free dynamic range: Typically 106 dBc at 30 dB gain (204.8 kS/s, 1 kHz, -1 dBFS)
• Spectral noise density: 8 nV/√Hz at 30 dB gain
Signal Conditioning & Filtering
• IEPE excitation: Software-selectable 0 mA, 4 mA ±15%, or 10 mA ±15%; IEEE 1451.4 Class 1 TEDS support
• Hardware analog and software-configurable digital anti-aliasing filters
• AC coupling: -3 dB cutoff 3.4 Hz; -0.1 dB cutoff approximately 10 Hz
– Key Features
• Simultaneous four-channel acquisition eliminates inter-channel timing errors
• Software-programmable sampling rates and gain settings enable rapid test reconfiguration
• IEPE conditioning supports microphones and accelerometers without external amplifiers
• Analog overvoltage protection to ±42.4 Vpk prevents input damage during unexpected signal transients
• Hardware anti-aliasing filters reduce computational overhead in post-processing
– Typical Applications
• Audio test and frequency response measurement
• Automotive noise, vibration, and harshness (NVH) analysis
• Machine condition monitoring via vibration signature analysis
• Acoustic measurements and environmental sound characterization
– Compatibility & Integration
The PXI-4462 integrates into the PXI chassis ecosystem, supporting modular, synchronized multi-module test systems for distributed measurement and analysis.
