To ensure accuracy at all available sampling rates, these devices incorporate the NI-PGIA 2 custom amplifier and NI-MCal self-calibration to minimise settling time and guarantee maximum accuracy. An onboard lowpass filter can be programmatically enabled to further improve measurement accuracy by eliminating high frequency noise. With the NI USB-628x devices, engineers can deliver an absolute accuracy of 980 µV at a range of ±10 V and 28 µV at a range of ±100 mV at a sampling rate of up to 625 kS/s.
The USB-6281 features 16 single-ended (SE) and eight differential input (DI) analogue input channels, two analogue output channels and 24 digital I/O (DIO) channels, while the USB-6289 features 32 SE and 16 DI analogue input channels, four analogue output channels and 48 DIO channels. Both devices offer 18-bit analogue inputs at up to 625 kS/s (500 kS/s when scanning) and 16-bit analogue output at 833 kS/s. High-accuracy USB-628x devices also provide enhanced waveform generation. Engineers can now define custom offset and range settings for analogue output and maximise the 16 bits of output resolution around a fixed DC offset to generate a more accurate representation of small signals and increase the accuracy of analogue waveforms.
High-accuracy NI M Series multifunction DAQ devices are ideal for applications including device test and characterisation and for sensor and signal measurements requiring instrument-class accuracy. Applications that can now benefit from the higher accuracy include scientific instrumentation such as geological monitoring, materials analysis, environmental sensing, calorimetry, optics, spectroscopy, structural sensing and gas detection, along with medical device instrumentation such as heart rate monitoring. USB-628x devices are also ideal for electronics characterisation and research.
Unlike typical multifunction USB data acquisition devices, NI M Series USB DAQ devices incorporate NI signal streaming, a patent-pending technology that provides multiple bidirectional high-speed data streams over USB. NI signal streaming, combined with the error correction, noise rejection, power management and power distribution inherent to the USB protocol, yields a flexible, secure and reliable bus. Without NI signal streaming, a multifunction data acquisition device can sustain only a single high-speed data stream, effectively making it a single-function device.
The new USB-628x devices are shipped with NI-DAQmx driver software and NI LabVIEW SignalExpress LE, an interactive measurement workbench for quickly acquiring, analysing and presenting data without additional programming. The NI-DAQmx driver also provides time-saving features such as code generation for both the LabVIEW graphical development environment and text-based languages such as ANSI C/C++, C#, Visual Basic .NET and Visual Basic 6.0; more than 3,000 measurement examples; device simulation; and connection diagrams.