Rohm RKX-EVK-001, User Manual

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© 2022 ROHM Co., Ltd. No. 64UG118E Rev.002
Feb.2022
User’s Guide
1.4.1.4
Frequency analysis
The Plotter also has an FFT (Fast Fourier Transform) functionality to show frequency data. The sub-channel view can be used to show only the
desired sub-channel frequency graph(s) and to further narrow down to any specific axis if required. For instance, ( Figure 38 ) shows the input signal
sensed by KX132-1211 accelerometer has two frequency components, 300Hz and 600Hz. The plotter is configured to show only data for
accelerometer Z-axis (AccZ), with logarithmic scale on Y-axis.
FFT data can be shown also from ADC Evaluation board data. Example FFT data of a sine wave with a frequency of 200 Hz input to ADC
Evaluation Board ( Figure 39 ).
Also, it is possible to change the x-axis to a logarithmic scale and the y-axis to a dB scale ( Figure 40) .
NOTE : The x-axis range for the plot starts from 0 Hz and ends in ODR/2 Hz. It is automatically adjusted if the ODR is modified.
Figure 38. Plotter view of KX132-1211 with FFT functionality
Figure 39. ADC plotter view with FFT functionality