The NI PCI-4461 is a 2-input/2-output dynamic signal analyzer delivering 24-bit resolution across dual simultaneously sampled analog input channels and dual analog output channels. Sampling and update rates reach 204.8 kS/s, with software-selectable input ranges spanning ±0.316 V to ±42.4 V peak and output voltage options of ±10 V, ±1 V, or ±0.1 V. Built-in IEPE current excitation conditioning (0 mA, 4 mA ±15%, or 10 mA ±15%) and TEDS support enable direct transducer integration for audio, acoustic, vibration, and machine condition monitoring.
Technical Specifications
Analog Input Performance
• 24-bit resolution, 204.8 kS/s maximum sampling rate
• Software-selectable ranges: ±0.316 V to ±42.4 V peak
• Differential or pseudodifferential configuration per channel, independently selectable
• AC or DC coupling; AC coupling -3 dB cutoff: 3.4 Hz
• Six gain settings per channel: -20 dB to +30 dB in 10 dB steps (0 dB = ±10 Vpk)
• Amplitude flatness: ±0.1 dB (DC to 92 kHz)
• Dynamic range: 118 dB
• THD: Typical -107 dB; -95 dB at 1 kHz
• Spectral noise density: 8 nV/√Hz at 30 dB gain with EAR enabled
• SFDR: Typically 106 dB at 204.8 kS/s, 1 kHz tone
• Input impedance: 1 MΩ//75 pF (differential); 1 MΩ//150 pF (pseudodifferential)
• CMRR: ≥70 dB at 50 Hz
• Hardware analog and digital anti-aliasing filters included
Analog Output Performance
• 24-bit resolution, 204.8 kS/s update rate
• Output voltage options: ±10 V, ±1 V, or ±0.1 V
• Software-programmable attenuation: 0, 20, or 40 dB
• Amplitude flatness: ±0.1 dB (DC to 92 kHz)
• THD: -95 dB at 1 kHz
• Output impedance: 11 Ω typical
• 8-times oversampling interpolators with 64-times oversampling delta-sigma modulators
• Analog and digital anti-imaging filters
Transducer Support
• IEPE conditioning: 0 mA, 4 mA ±15%, or 10 mA ±15% software-selectable
• IEEE 1451 TEDS compatible
– Typical Applications
• Audio and acoustic testing
• Automotive diagnostics and NVH analysis
• Machine condition monitoring
• Noise, vibration, and harshness measurement
