Analog Devices AD7273, Руководство пользователя

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EVAL-AD7273/AD7274
Rev. 0 | Page 9 of 16
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DIGITAL
STORAGE
OSCILLOSCOPE
(DSO)
WAVEFORM DISPLAY
DIGITAL
STORAGE
OSCILLOSCOPE
(DSO)
FFT DISPLAY
CONTROL
BUTTONS
Figure 4. AD7273/AD7274 Main Window
Digital Storage Oscilloscope
The middle section of the screen is a digital storage oscilloscope
(DSO) that allows you to display a waveform, a histogram or a
fast Fourier transform (FFT). When samples are uploaded from
the EVAL-CONTROL-BRD2, they are displayed here. The
samples can be displayed either as integer values or as voltages.
At the bottom left corner of the graph are the zoom options.
These allow you to zoom in and out to get a closer look at a
sample, if required. The right-hand side of the middle section
contains information about the samples taken, for example,
minimum/maximum position or velocity, the spread, the
standard deviation, and the mean.
Fast Fourier Transform or Histogram
The lower section of the window is also a digital storage
oscilloscope (DSO) that allows you to display a waveform, a
histogram, or an FFT. The FFT (the default option) is typically
used for examining the ADC’s performance in the frequency
domain while the histogram gives an indication of the ADC’s
performance in response to dc inputs. The option displayed can
be changed by clicking on the Waveform , Histogram , and FFT
buttons. The right-hand side of the lower section contains
information about the samples taken, for example, ac
specifications. Figure 4 shows a screen shot of the main window.
TAKING SAMPLES
When you click the
Sample
button, the software instructs the
EVAL-CONTROL-BRD2 to take the required number of
samples at the required frequency from the evaluation board.
The samples taken are then uploaded and displayed. An FFT
and histogram are also calculated and displayed. If you click the
Continuous
button
,
the software repeats the process indefi-
nitely until you click the Stop button (the Continuous button
switches to Stop when clicked).
EVAL-AD7273/AD7274 SCHEMATIC, SILKSCREEN,
AND LAYOUT
These can be found in Figure 5, Figure 6, Figure 7, Figure 8
,
and
Figure 9.