Detailed Specifications of NI PXI-6250 Multifunction DAQ Module
The NI PXI-6250 is a high-performance multifunction data acquisition (DAQ) module belonging to NI’s M-Series product line, engineered for the PXI bus architecture. It integrates high-speed analog input, flexible digital I/O, and precision timing functions, delivering cost-effective and reliable measurement solutions for laboratory automation, industrial testing, and scientific research applications .
1. Basic Information
- Module Series: M-Series multifunction DAQ, optimized for PXI bus systems.
- Physical Dimensions: 3.8 × 6.1 inches (9.65 × 15.49 cm), compatible with standard 3U PXI chassis.
- Weight: Approximately 5 ounces (0.14 kg) .
- Operating Power Requirements: +5 V (0.725 A), +3.3 V (0.03 A), +12 V (0.35 A) .
- Connectors: 68-pin VHDCI I/O connector for signal integration .
2. Core Technical Specifications
2.1 Analog Input
- Channel Configuration: 16 single-ended channels or 8 differential channels, supporting referenced single-ended, non-referenced single-ended, and differential configurations .
- Resolution: 16-bit ADC with no missing codes guaranteed (DNL) .
- Sampling Rate: Up to 1.25 MS/s (single-channel mode); 1.0 MS/s aggregate throughput in multi-channel multiplexing .
- Input Range: Switchable across seven ranges to accommodate diverse signal amplitudes: ±0.1 V, ±0.2 V, ±0.5 V, ±1 V, ±2 V, ±5 V, ±10 V .
- Overvoltage Protection: ±25 V (powered on) and ±15 V (powered off) for up to two analog input pins, with maximum input current of ±20 mA per pin during overvoltage .
- Input impedance: >10 GΩ (parallel with 100 pF) when powered on; 820 Ω when powered off .
- CMRR (DC to 60 Hz): 100 dB .
- Small signal bandwidth (-3 dB): 1.7 MHz .
- Settling time: 1 μs (±60 ppm of step) for ±1 V to ±10 V ranges; 8 μs (±15 ppm of step) for ±0.1 V/±0.2 V ranges .
- Memory Buffer: 4,095-sample input FIFO and 4,095-entry scan list memory .
2.2 Digital I/O
- I/O Lines: 24 programmable digital lines, compatible with 5 V TTL/CMOS logic levels .
- Functionality: Configurable per line as input or output, supporting correlated I/O, digital triggering, and pattern generation. Grounding reference is D GND .
- Timing: Synchronized with 20 MHz internal clock for high-precision signal handling .
2.3 Counter/Timer
- Configuration: 2 independent 32-bit counters/timers with 80 MHz base clock .
- Clock Sources: Internal (0.1 MHz, 20 MHz, 80 MHz) or external (0–20 MHz) clock options .
- Supported Tasks: Event counting, frequency measurement (up to 10 MHz), period measurement (minimum 100 ns), and time-interval measurement .
2.4 Synchronization & Triggering
- Trigger Options: Analog edge trigger (adjustable threshold, rising/falling edge) and digital edge trigger (TTL-compatible) .
- Signal Conditioning Compatibility: Seamlessly integrates with NI SCC (Signal Conditioning Cartridge) and SCXI modules (e.g., SCXI-1125) for sensor signal amplification, filtering, and high-voltage measurement capabilities .
- Data Transfer: Supports DMA (scatter-gather), interrupts, and programmed I/O for efficient data transmission .
3. Software & Driver Support
- Drivers: NI-DAQmx and NI-DAQmx Base driver software, providing intuitive APIs for device configuration and data acquisition .
- Programming Compatibility:
- NI Software: LabVIEW, LabWindows/CVI, Measurement Studio, and LabVIEW SignalExpress .
- Third-Party Languages: C/C++, C#, MATLAB, and Python (via NI-DAQmx bindings) .
- Calibration: Integrated NI-MCal calibration technology; recommended calibration interval is 2 years to maintain accuracy .
4. Typical Application Scenarios
The NI PXI-6250 excels in cost-sensitive, high-speed measurement applications, including:
- Industrial Automation: Production line monitoring (temperature, pressure, flow rate) and equipment control (motors, valves) .
- Scientific Research: Sensor signal acquisition in physics, chemistry, and biology experiments, providing accurate data for analysis .
- Design Verification & Testing: Performance validation of electronic devices, circuit boards, and components during R&D .
- Manufacturing Quality Control: In-line product testing to ensure compliance with quality standards .
5. Selection & Compatibility Notes
- Ideal For: Applications requiring high-speed sampling (<1.25 MS/s) and 16-bit precision, with moderate channel density needs.
- Upgrade Path: For higher analog output functionality, consider the NI PXI-6251 (2 analog output channels); for higher sampling rates (up to 2 MS/s), opt for the NI PXI-6280 .
- System Integration: Compatible with all NI 3U PXI chassis (e.g., PXI-1042) and third-party PXI-compliant systems. Note that only one hardware timebase can be used at a time, and immediate I/O and task-based I/O cannot share the same channels .
