UG-003
4.
Note that other settings can be changed on the ADCBase 0
page (see Figure 12) and the ADC A and ADC B pages
(see Figure 13) to set up the part in the desired mode. The
ADCBase 0 page settings affect the entire part, whereas the
settings on the ADC A and ADC B pages affect the selected
channel only. See the appropriate part data sheet; the
Application Note, High Speed ADC SPI Control Software; and
the
AN-877
Application Note, Interfacing to High Speed ADCs
via SPI, for additional information on the available settings.
Figure 13. SPI Controller, Example ADC A Page
5.
Click the Run button in the VisualAnalog toolbar (see
Figure 14).
Figure 14. Run Button (Encircled in Red) in VisualAnalog Toolbar,
Collapsed Display
Adjusting the Amplitude of the Input Signal
The next step is to adjust the amplitude of the input signal for
each channel as follows:
1.
Adjust the amplitude of the input signal so that the
fundamental is at the desired level. Examine the Fund Power
AN-878
reading in the left panel of the VisualAnalog Graph - AD9268
Average FFT window (see Figure 15).
2.
Repeat this procedure for Channel B.
3.
Click the disk icon within the Graph window to save the
performance plot data as a .csv formatted file. See Figure 16
for an example.
0
–20
–40
–60
–80
–100
–120
–140
Rev. A | Page 10 of 40
Evaluation Board User Guide
Figure 15. Graph Window of VisualAnalog
125MSPS
70.1MHz @ –1dBFS
SNR = 76.5dB (77.5dBFS)
SFDR = 88.0dBc
THIRD HARMONIC
SECOND HARMONIC
0
10
20
30
FREQUENCY (MHz)
Figure 16. Typical FFT, AD9268/AD9258
40
50
60
Need help?
Do you have a question about the AD9204-65EBZ and is the answer not in the manual?
Questions and answers