Analog Devices EVAL-AD7383FMCZ, User Manual

Page: 14 / 16

UG-1770 EVAL-AD7383FMCZ Evaluation Board User Guide
Rev. A | Page 14 of 16
Waveform Tab
The Waveform tab displays data in the form of time vs. discrete
data values with the results, as shown in Figure 19.
CAPTURE Pane
The CAPTURE pane contains the capture settings. These settings
reflect onto the registers automatically before data capture.
The Sample Count pulldown menu in the General Capture
Settings
section allows the user to select the number of samples
per channel per capture (see Figure 19).
The SPI Frequency pulldown menu allows the user to select
the SPI clock frequency used to transfer data between the
FPGA device and the
AD7383 during device register reads and
writes and during data capture (see Figure 19). This frequency
must be set relatively higher than the set throughput rate.
The user can enter the input sample frequency in kSPS in the
Sampling Frequency(ksps) box (see Figure 19). Refer to the
AD7383 data sheet to determine the maximum sampling
frequency for the selected mode.
The Over Sampling Ratio pulldown menu, when enabled, can
be set between 2 and 32 and provide improved signal-to-noise
ratio (SNR) performance (see Figure 19). Refer to the AD7383
data sheet to determine the maximum oversampling ratio for
the selected oversampling mode.
The Over Sampling Mode pulldown menu allows the user to
select the mode of oversampling (see Figure 19). This setting is
only applicable when oversampling is enabled.
Click Run Once to start a data capture of the samples at the
sample rate specified in the Sample Count pulldown menu (see
Figure 19). These samples are stored on the FPGA device and
are only transferred to the PC when the sample frame is complete.
Click Run Continuously to start a data capture that gathers
samples continuously with one batch of data at a time (see
Figure 19). This operation runs the
Run Once operation
continuously.
RESULTS Pane
The Display Channels section allows the user to select the
channels to capture (see Figure 19). The channel data is shown
only if that channel is selected before the capture.
The Waveform Results section displays the amplitude, Sample
Frequency , and noise analysis data for the selected channels
(see Figure 19).
Click Export to export the captured data (see Figure 19). The
waveform, histogram, and FFT data is stored in .xml files along
with the values of parameters at capture.
The data Waveform graph shows each successive sample of the
ADC output (see Figure 19). The user can zoom in on and pan
over the Waveform graph using the embedded waveform tools
above the graph. Select the channels to display in the
Display
Channels section.
Under the Display Units dropdown menu, select Codes above
the Waveform graph (see Figure 19) to select whether the
Waveform graph displays in units of Codes , Hex , or Volts . The
axis controls are dynamic.
When either y-scale dynamic or x-scale dynamic is selected,
the corresponding axis width automatically adjusts to show the
entire range of the ADC results after each batch of samples.
Histogram Tab
The Histogram tab contains the Histogram graph and the
RESULTS
pane, as shown in Figure 20.
The RESULTS pane displays the information related to the dc
performance.
The Histogram graph displays the number of hits per code within
the sampled data (see Figure 20). The Histogram graph is useful
for dc analysis and indicates the noise performance of the AD7383.
FFT Tab
The FFT tab displays fast Fourier transform (FFT) information for
the last batch of samples gathered (see Figure 21).
ANALYSIS Pane
The
General Settings
section allows the user to set up the
preferred configuration of the FFT analysis, including how many
tones are analyzed (see Figure 21). The fundamental is set
manually.
The Windowing section allows the user to select the windowing
type used in the FFT analysis, the number of Harmonic Bins ,
and the number of
Fundamental Bins
that must be included
(see Figure 21).
The Single Tone Analysis and Two Tone Analysis sections
allow the user to select the fundamental frequency included in
the FFT analysis (see Figure 21). Use the
Two Tone Analysis
settings when analyzing two frequencies.
RESULTS Pane
The Signal section displays the Sample Frequency , Fund
Frequency , and Fund Power (see Figure 21).
The Noise section displays the SNR and other noise performance
results (see Figure 21).
The Distortion section displays the harmonic content of the
sampled signal and dc power when viewing the FFT analysis
(see Figure 21).
EXITING THE SOFTWARE
To exit the ACE software, click File and then click Exit .