Quick Start Guide To The Ad9522 Pll - Analog Devices AD9522 Series User Manual

Evaluation Board User Guide

QUICK START GUIDE TO THE AD9522 PLL

When the evaluation software is installed, the evaluation board
is connected, and the software is loaded, use the following steps
to configure and lock the PLL. These steps assume that the input
signal is present, the evaluation board has not been modified,
and that the PLL loop filter is suitable for the user's application.
This quick start guide covers only simple PLL operation to start
the PLL. See the AD9522 data sheet and the Evaluation Software
Components section for a detailed explanation of the various
AD9522 features.
The following case is an example for the AD9522-4, using the
values in Table 1.
Table 1.
Parameter
Input Frequency
Output Frequency
Reference Divider
Phase Detector Frequency
Feedback Divider
VCO Frequency
VCO Divider
Channel Divider
1. Turn the PLL on by selecting Normal Op from the PLL
MODE box found at the top of the main window (see
Figure 8).
2. Enter the intended reference input frequency (in
megahertz) in the REF 1 (MHz) box at the upper left
corner of the main window.
3. Click the triangular buffer symbol immediately to the right
of the input reference frequency (see Figure 4) to load the
Reference Input Control window shown in Figure 5. Turn
the REF1 reference input buffer on by selecting the Enable
REF 1 check box, and then clicking OK.
Figure 4. Buffer Symbol
Value
19.44 MHz on REF1
148.5 MHz
72
270 kHz
5500
1485 MHz
2
5
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Figure 5. AD9522 Reference Input Control Window
4. When the window closes, the WRITE button under the
Register W/R control section in Figure 8 blinks red. This
indicates that there are settings that have not been loaded
to the AD9522 evaluation board. Click the blinking red
WRITE button to load these settings to the evaluation
board.
5. Select the VCO as the input to the clock distribution
circuitry by clicking the mux symbol that is located
immediately to the right of the VCO (MHz) box (see
Figure 6).
Figure 6. Buffer Symbol
When the VCO is selected, the border of the VCO (MHz)
box changes from gray to black. The current VCO frequency
is shown in the VCO (MHz) box.
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