National Instruments NI 9233 Understanding NI 9233 Data Rates

NI 9233 Operating Instructions and Specifications 14 ni.com

The filter significantly attenuates all signals above the stopband

frequency. The primary goal of the filter is to prevent aliasing.

Therefore, the stopband frequency scales precisely with the data

rate. The stopband rejection is the minimum amount of attenuation

applied by the filter to all signals with frequencies within the

stopband.

Any signal that appears in the alias-free bandwidth of the NI 9233

is not an aliased artifact of signals at a higher frequency. The

alias-free bandwidth is defined by the ability of the filter to reject

frequencies above the stopband frequency and it is equal to the data

rate minus the stopband frequency.

Understanding NI 9233 Data Rates

The frequency of a master timebase (fM) controls the data rate (fs)

of the NI 9233. The NI 9233 includes an internal master timebase

with a frequency of 12.8 MHz, but the module also can accept an

external master timebase or export its own master timebase. To

synchronize the data rate of an NI 9233 with other modules that use

master timebases to control sampling, all of the modules must