NI USB-6225 16-Bit Multifunction DAQ

The NI USB-6225 is a 16-bit multifunction DAQ module engineered for USB connectivity in measurement and control applications spanning laboratory automation, research, design verification, and manufacturing test. It combines 40 differential (80 single-ended) analog input channels with 2 analog output channels, up to 24 digital I/O lines, and dual 32-bit counters/timers - all accessible through NI-DAQmx driver software. Signal conditioning expansion via SCC or SCXI modules enables sensor and high-voltage measurement capabilities.

Technical Specifications

• 40 differential or 80 single-ended channels, 16-bit resolution


• Input ranges: ±0.2 V, ±1 V, ±5 V, ±10 V


• Maximum sample rate: 250 kS/s (single or aggregate multichannel)


• Timing accuracy: 50 ppm of sample rate


• Input FIFO: 4,095 samples


• Overvoltage protection: All channels; ±20 mA maximum during overvoltage


• No missing codes guaranteed; maximum working voltage ±11 V -# Analog Outputs


• 2 channels, 16-bit resolution with guaranteed monotonicity


• Output range: ±10 V; output impedance 0.2 Ω


• Maximum update rates: 833 kS/s (single), 740 kS/s (dual)


• Settling time: 4 µs convert interval (±90 ppm of step/±6 LSB on full-scale steps)


• Overdrive protection to ±25 V at 10 mA -# Digital I/O


• Up to 24 static or 48 total channels


• Hardware-timed digital I/O: 32 lines at 1 MHz


• Correlated DIO: 8 clocked lines at 1 MHz


• Debounce filters: 125 ns, 6.425 µs, 2.56 ms, or disabled (selectable per input)


• Digital triggering supported


• ±20 V overvoltage protection on up to two pins -# Counters/Timers


• Two 32-bit counters with 10 MHz and 100 kHz base clocks


• Base clock accuracy: 50 ppm


• Frequency generator output available on PFI or RTSI terminals -# Power & Physical


• USB external supply: 11–30 VDC, 20 W


• +5 V terminal: 1 A max; combined +5 V/PFI/P0/P1/P2: 2 A max


• 2 A, 250 V supply fuse


• Recommended warm-up time: 15 minutes

Key Features

• Guaranteed no missing codes (16-bit DNL)


• Timing accuracy maintained across all operating modes


• Integrated overvoltage and overdrive protection


• Selectable per-channel debounce configurations


• Direct signal conditioning module support

Typical Applications

• Sensor characterization and calibration


• Real-time control systems in test environments


• Multi-channel data logging in production test


• Frequency and timing measurement tasks

Compatibility & Integration NI-DAQmx driver software enables simplified configuration. Expansion capabilities through SCC and SCXI signal conditioning modules extend measurement range and sensor compatibility. PFI terminals support correlated triggering and frequency generation.