Evaluation Board User Guide

ManualsBrandsAnalog Devices ManualsComputer HardwareAD9551

UG-002

One Technology Way • P. O. Box 9106 • Norwood, MA 02062-9106, U.S.A. • Te l: 781.329.4700 • Fax: 781.461.3113 • www.analog.com

Evaluating the AD9551 Multiservice Clock Generator

See the last page for an important warning and disclaimers. Rev. 0 | Page 1 of 12

FEATURES

Simple power connection using USB connection and

on-board LDO voltage regulators

LDOs are easily bypassed for power measurements

AC-coupled differential LVPECL SMA connectors

SMA connectors for

2 reference inputs

2 PLL lock detect outputs

Microsoft Windows®–based evaluation software

with simple graphical user interface

On-board PLL loop filter

Easy access to digital I/O and diagnostic signals

via I/O header

Status LEDs for diagnostic signals

USB computer interface

Dip switch configurable for manual operation

Software calculator provides flexibility, allowing programming

almost any rational input/output frequency ratio

GENERAL DESCRIPTION

This user guide describes the hardware and software of the

AD9551 evaluation board and includes detailed schematics and

PCB layout artwork. The AD9551 Revision D evaluation board

is a compact, easy to use platform for evaluating all features of the

AD9551 multiservice clock generator.

The AD9551 accepts one or two reference input signals to

synthesize one or two output signals. The AD9551 uses a

fractional-N PLL that precisely translates the reference frequency

to the desired output frequency. The input receivers and output

drivers provide both single-ended and differential operation.

Reference conditioning and switchover circuitry internally

synchronizes the two references so that if one reference fails,

there is virtually no phase perturbation at the output.

The AD9551 uses an external crystal and an internal DCXO to

provide for holdover operation. If both references fail, the device

maintains a steady output signal. This may mislead you to believe

that the PLL is locked and the board is configured properly. A

simple test is to move the input REF A or REF B clock a few kilo-

hertz and verify that the changes in output frequency track the input.

DIGITAL PICTURE OF THE EVALUATION BOARD

08129-001

Figure 1.

AD9551 Evaluation Board, Revision D

Summary of content (12 pages)

PAGE 1
Evaluation Board User Guide UG-002 One Technology Way • P.O. Box 9106 • Norwood, MA 02062-9106, U.S.A. • Tel: 781.329.4700 • Fax: 781.461.3113 • www.analog.
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UG-002 Evaluation Board User Guide TABLE OF CONTENTS Features .............................................................................................. 1 Using an SPI Port ..........................................................................5 General Description ......................................................................... 1 Using Dip Switches (Manual Control) .......................................5 Digital Picture of the Evaluation Board ........................................
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Evaluation Board User Guide UG-002 EVALUATION BOARD HARDWARE The following instructions are for setting up the physical connections to the AD9551 evaluation board. SETTING UP THE SIGNAL CONNECTIONS SETTING UP THE POWER AND PC CONNECTIONS After setting up the power and PC connections, use the following procedure to set up the signal connections: Set up the power and PC connections as follows: 1. 1.
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UG-002 Evaluation Board User Guide EVALUATION BOARD SOFTWARE The instructions included in this section are for setting up the AD9551 evaluation board software. 4. If the evaluation board was not found, a dialog box appears that allows you to select an evaluation board to use while the software runs in standalone mode. Standalone mode is useful for viewing and generating register setup files. 5.
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Evaluation Board User Guide UG-002 GUIDE TO PROGRAMMING THE AD9551 The AD9551 can be programmed via an SPI port or by setting the logic levels on the frequency select pins of the device. To program the device using the serial port, the evaluation board software must be installed. 5. Set the amplitude and frequency. An amplitude setting of 6 dBm is sufficient. Set the frequency to 622.08 MHz. 6. To connect a signal to REF B, connect the signal to SMA Connector J2.
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UG-002 Evaluation Board User Guide SOFTWARE OPERATION When a subsection window closes after clicking OK, you may notice that the LOAD button on the main window starts blinking. This indicates that there are settings that have not been loaded to the AD9551 evaluation board. Click LOAD to load these settings to the evaluation board. 08129-004 The main window of the AD9551 evaluation board software is comprised of subsections that correspond to the major functional blocks of the AD9551 (see Figure 4).
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Evaluation Board User Guide UG-002 MENU BAR OF MAIN WINDOW File Menu The File menu allows you to load a previously saved AD9551 setup file or to save a new AD9551 setup file. A setup file (.STP) is a text file that contains the AD9551 register setup file, plus any evaluation board settings. To load a previously saved setup file, select Load Setup from the File menu. Note that you must still perform a VCO calibration. Alternatively, to save a new setup file, select Save Setup from the File menu.
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UG-002 Evaluation Board User Guide BUTTON BAR OF MAIN WINDOW The buttons described in this section provide easy access to common features. Load and Save Clicking Load and Save allows you to load and save an AD9551 setup file. A setup file (.STP) is a text file that contains the AD9551 register setup file, plus any evaluation board settings. Update Clicking Update toggles the I/O update bit (Register 0x05, Bit 0) of the AD9551.
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Evaluation Board User Guide UG-002 PFD and Charge Pump Window Clicking Click for Details in the DLL box of the main window accesses the DLL window (see Figure 11). This window can be used to manually override the automatic time alignment between the REF A and REF B clock input signals to the PLL1 phase detector. Clicking Click for Details in the PFD & Charge Pump box of the main window accesses the PFD and Charge Pump window (see Figure 13). 08129-013 DLL Window 08129-015 Figure 11.
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UG-002 Evaluation Board User Guide OutSel Pin: Box Clicking Click for Details in the Feedback Divider box of the main window accesses the Feedback window, which allows you to change the feedback divider settings (see Figure 15). The OutSel Pin: drop-down box (see Figure 18) in the main window controls the logic level on the OUTSEL pin of the AD9551. However, this value can be overwritten by using the SPI control register. 08129-019 Feedback Window Figure 18.
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Evaluation Board User Guide The Calculator window, shown in Figure 21, appears. 5. The Enable Control? window, shown in Figure 23, appears. 08129-024 7. UG-002 Figure 23. AD9551 Serial Port Programming Warning Click Yes to enable serial port register programming. 7. The Calculator window, shown in Figure 24, appears. 08129-022 6. Figure 21. Calculator Window 8. Type 122.88 into the Ref A Base Frequency: box and 122.88 into the Output 1 Base Frequency: box. 9.
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Evaluation Board User Guide 08129-027 08129-026 UG-002 Figure 25. Register Debug Window Figure 26. Input PLL + DCXO Window 11. Bit 3 of Register 0x17 must be set to 1 to enable the PLL locked pin as a test port. By default, the 26 MHz crystal frequency is present at the output. 12. The ac signal has a dc offset of approximately 1.6 V. Be aware that some test equipment has a limit of 0 V dc; therefore, a dc block must be used in such cases. SETTING THE 19.