The NI-9202, 9252 and the 9253 use a combination of analog and digital filtering to provide an accurate representation of in-band signals while rejecting out-of-band signals. The filters discriminate between signals based on the frequency range, or bandwidth, of the signal. The filtering is always enabled and the filter configuration applies to all channels on the module.The configuration of the on-board filters is done in two steps.
- Select a suitable data rate (sampling rate) for your project.
- Open the the datasheet for your module
- Choose a data rate that is suitable for your measurement
- While in the datasheet, find the response curves for the different available filters and choose the response that is most suitable for your measurement
- Select and configure the filter in NI-DAQmx using the following DAQmx channel properties.
To see a LabVIEW example for how to configure the filters navigate to the the following path in the LabVIEW example finder: Hardware Input and Output>>DAQmx>>Analog Input>>Analog Input - Filtering VI. There is also a LabVIEW example
located on the NI Community Page that demonstrates configuring the filters.
The configuration of the on-board filter is different for an FPGA-Target. Examples can be found via NI Example Finder
using keyword "9202, 9252 or 9253".