National Instruments USB-6211

The National Instruments USB-6211 is a bus-powered USB Data Acquisition module delivering 16 single-ended or 8 differential analog inputs, 2 analog outputs, 4 digital input channels, and 4 digital output channels. Built for portable data logging, field monitoring, embedded OEM systems, and academic research, this device achieves 250 kS/s maximum sampling rate across analog inputs with 16-bit resolution and ±10 V input ranges. The USB-6211 integrates two 32-bit counter/timer channels for edge counting, period measurement, and pulse detection, with internal base clocks of 80 MHz, 20 MHz, or 0.1 MHz. High input impedance (>10 GΩ), excellent crosstalk isolation (-75 dB adjacent, -90 dB non-adjacent at 100 kHz), and 100 dB common-mode rejection enable precision measurements in noisy environments. Analog outputs support ±200 mV to ±10 V ranges at 250 kS/s per channel. Digital I/O pins tolerate ±20 V input protection and deliver 16 mA maximum per pin. A 4,095-sample input FIFO and 4,095-entry scan list support complex multi-channel acquisition sequences. The device operates with NI-DAQmx driver software, standardizing configuration and measurement workflows across NI platforms.

– Technical Specifications

Analog Input
• 8 differential or 16 single-ended channels
• 16-bit resolution; 250 kS/s maximum sample rate (single channel), 250 kS/s aggregate
• Input ranges: ±10 V, ±5 V, ±1 V, ±0.2 V
• Input impedance (device on): >10 GΩ in parallel with 100 pF
• Input impedance (device off): 1200 Ω
• Input bias current: ±100 pA
• Crosstalk at 100 kHz: -75 dB (adjacent), -90 dB (non-adjacent)
• Small-signal bandwidth (-3 dB): 450 kHz
• Overvoltage protection: ±30 V (device on), ±20 V (device off) on up to two AI pins
• Input current during overvoltage: ±20 mA maximum per AI pin
• CMRR (DC to 60 Hz): 100 dB
• Input FIFO: 4,095 samples; Scan list memory: 4,095 entries

Analog Output
• 2 channels; 16-bit resolution
• Output voltage range: ±200 mV to ±10 V
• Maximum update rate: 250 kS/s per channel
• DNL: ±1 LSB; 16-bit monotonicity guaranteed

Digital I/O
• 4 digital input channels (PFI ); 4 digital output channels (PFI )
• Input voltage protection: ±20 V on up to 8 pins
• Maximum current per DIO pin: 16 mA
• Pull-down resistor: 47 kΩ ±1%

Counters/Timers
• 2 general-purpose 32-bit counter/timer channels
• Measurements: edge counting, two-edge separation, period, semi-period, pulse
• Base clocks: 80 MHz, 20 MHz, or 0.1 MHz (internal)

– Key Features

• Bus-powered USB operation; no external power supply required
• Multichannel settling: ±1 LSB at 7 μs convert interval
• High-impedance analog front end minimizes measurement loading
• Integrated timing and synchronization for complex trigger scenarios

– Typical Applications

• Portable data logging and field instrumentation
• OEM embedded measurement systems
• Laboratory and academic research
• Environmental and structural monitoring

– Compatibility & Integration

• NI-DAQmx driver software support
• USB connectivity for broad host compatibility