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Ref
10 dBm
Att
35 dB
*
*
1 AP
CLRWR
A
RBW 3 kHz
VBW 10 kHz
SWT 18 s
Cent er
80 MHz
Spa n
160 MH z
16 M
*
Hz/
−90
−80
−70
−60
−50
−40
−30
−20
−10
0
10
1
Marke r 1 [T1 ]
2.
71 d Bm
4 0.00 00000 00 M Hz
2.3
DAC5686 GUI Register Descriptions
2.3.1
Register Controls
DAC5686 EVM Operational Procedure
5. Reduce the CLK2 frequency to less than 320MHz. Enable the NCO and change the NCO DDS to
536870912. Doing this will generate a tone at Fdac/8. For CLK2 = 320 MHz, the tone corresponds to
40 MHz. The output spectrum should be similar to the one in
Figure 4. Spectrum with CLK2 = 320 MHz, X4 Interpolation, Single Sideband Mode and NCO Frequency =
536870912
6. Changing the NCO DDS to 268435456 (232 ? 20/320) will now result at an output tone at 20 MHz.
The following section provides a brief description of each control:
•
Load Regs: Loads register values from a saved file to the DAC5686 and updates the GUI.
•
Save Regs: Saves current GUI registers settings to a text file for future use.
•
Read All: Reads the current registers of the DAC5686. This is used to verify settings on the front
panel.
•
Send All: Sends the current front panel registers to the device. This is generally only used when the
EVM power has recycled or the device has been reset and the user wants to load the displayed
settings to the device.
SLWU006E – December 2004 – Revised March 2007
DAC5686 EVM
13
