AD9520-4/PCBZ Analog Devices Inc, AD9520-4/PCBZ Datasheet - Page 12

• Manufacturer Part Number: AD9520-4/PCBZ
• Description: BOARD EVAL FOR AD9520-4
• Manufacturer: Analog Devices Inc

Specifications of AD9520-4/PCBZ

• Design Resources: Synchronizing Multiple AD9910 1 GSPS Direct Digital Synthesizers (CN0121) Phase Coherent FSK Modulator (CN0186)
• Main Purpose: Timing, Clock Generator
• Embedded: No
• Utilized Ic / Part: AD9520-4
• Primary Attributes: 1.4 ~ 1.8 GHz Output Frequency
• Secondary Attributes: Accepts CMOS, LVDS, or LVPECL References Up to 250 MHz
• Silicon Manufacturer: Analog Devices
• Application Sub Type: PLL Clock Synthesizer
• Kit Application Type: Clock & Timing
• Silicon Core Number: AD9520-0, AD9520-2, AD9520-2
• Silicon Family Name: AD9520-X
• Rohs Compliant: Yes
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

UG-076
OUTPUT DRIVER WINDOW
The output driver window shown in Figure 22 is accessed by
clicking any of the numbered triangular output driver symbols
on the right side of the main window (see Figure 21).
It is important to power down unused outputs on the evaluation
board because they can be a major source of unwanted spurs.
LVPECL and CMOS outputs have different termination require-
ments, and OUT9 through OUT11 have been terminated
differently from OUT0 through OUT8.
Figure 22. Output Driver Window
Figure 21. Driver Symbol
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OUT 0 through OUT8 are ac-coupled with 200 Ω pull-down
resistors on each output. This termination scheme is ideal for
LVPECL drivers. However, this scheme degrades the CMOS
driver performance. Improved CMOS driver performance is
achieved by removing the 200 Ω pull-down resistors.
OUT9 though OUT11 have no termination resistors, and are
ideally configured for CMOS operation. If you want to use these
drivers in LVPECL mode, pull-down resistors must be added to
the board. If you want to put 50 Ω termination at the SMA
connectors of OUT9 through OUT11, add series decoupling
capacitors so that the termination on OUT9 through OUT11 is
identical to OUT0 through OUT8.
DEBUG WINDOW
The Debug window shown in Figure 23 is accessed by clicking
the Debug option from the View menu.
The Serial I/O section of this window is a convenient way to
read and write registers directly.
Evaluation Board User Guide
Figure 23. Debug Window