The AD9546 Evaluation Board is a compact, easy-to-use platform for evaluating all features of the AD9546 multiple input, 10-Output, Dual Channel, Numeric Clock Synchronizer. The AD9546 supports existing and emerging International Telecommunications Union (ITU) standards for the delivery of frequency, phase, and time of day over service provider packet networks, including ITU-G.8262, ITU-T G.812, ITU-T G.813, ITU-T G.823, ITU-T G.824, ITU-T G.825, and ITU-T G.8273.2.
The 10 clock outputs of the AD9546 are synchronized to any one of up to four input references. The digital phase-locked loops (DPLLs) reduce timing jitter associated with the external references. The digitally controlled loop and holdover circuitry continuously generate a low jitter output signal, even when all reference inputs fail. The AD9546 system clock is provided by a 52 MHz crystal. Alternatively, an external clock signal may be provided at a SMA connector (relative components must be populated to enable this functionality).
The following instructions are for setting up the physical connections to the AD9546/PCBZ Evaluation Board. The user must install the Evaluation Software prior to connecting the Evaluation Board for the first time.
The 6 V supply powers the following:
By default, the 3.3 V ADP2384 switcher output supply supplies a 1.8 V Analog Devices ADM7171 Low Noise LDO to power the AD9546. The ADP2384 Switching Regulator can also be configured to output 1.8 V and directly power the AD9546 to evaluate the AD9546 when powered directly from a switching power supply. The AD9546 can also be powered from external 3.3 V or 1.8 V supplies. To increase the SPI speed when the AD9546 is managed through the USB connector, an additional power supply scheme is proposed. In this scheme, the AD9546 VDD pins are supplied at 1.8 V from the above LDO, while the serial port and Mx pin VDDIOA and VDDIOB pins are supplied directly from the 3.3 V switching regulator.
In the following, various power supply solutions of the AD9546 are presented together with the configurations of the 0 Ω resistors.
The AD9546 Evaluation Board has four reference input sources. By default, REF A/AA (Connectors J301 and J302, respectively) are configured as single ended differential AC-coupled reference inputs. Each can be connected to a signal generator directly. In contrast, REF B/BB (Connectors J303 and J304, respectively) are configured for single-ended CMOS inputs by default. Each reference input logic type is configurable via the Evaluation Software.
By default, the AD9546 system clock input is configured to the on-board 52 MHz crystal. An additional path, not populated, may be used to provide a system clock input at J305 connector.
The connector P503 may be used to directly access the AD9546 from an external device. A Raspberry PI 3 Model B+ may be used to interface with the AD9546 Evaluation Board at connector P503.
The signals available at connector P503 are the SPI pins (SCLK, SDIO, SDO, CSB) and the M0, M1, M2 and M3 control pins. Jumpers at connectors P507 and P508 select how these signals are managed: through connector P503 or through USB interface, that is from the PC based user interface.
Table 1 and Table 2 present the position of the jumpers when connector P503 is used and when the USB interface is used:
Table 1. SPI Pin Management Settings at Connector P507
|SPI PINS||Managed via P503||Managed via USB|
|SCLK||2 - 1||2 - 3|
|SDIO (MOSI)||5 - 4||5 - 6|
|SDO (MISO)||8 - 7||8 - 9|
Table 2. AD9546 Mx Pin Management Settings at Connector P508
|Mx Pins||Managed via P503||Managed via USB|
|M0||2 - 1||2 - 3|
|M1||5 - 4||5 - 6|
|M2||8 - 7||8 - 9|
A generic FPGA or a microcontroller can interface with the AD9546 through connector P512 that provides access to all SPI pins of the AD9546. See board schematics for details.
The AD9546 Evaluation Board contains two EEPROMS:
To protect the EEPROMs from being overwritten, place jumpers at P502 and P506 connectors. To make sure the CYUSB EEPROM is enabled, place jumper at P501 connector. To program the CYUSB EEPROM, take out the jumper P502 to enable the operation and use the available programming tool. To program the PI EEPROM, take out the jumper P506 to enable the operation and use the available programming tool.
The control pins M0 - M6 may be managed in several ways on the on the AD9546 Evaluation Board:
Table 3. M0 - M6 Pins Access
|Control Pins||Connector||P601 Jumper|
Note that M5 and M6 pins are multiplexed with the SPI pins SDO and, respectively, CSB. The default board settings enable the SPI functionality, so the M5 and M6 pins are not usable.
The 0 Ω resistors R608, R657, RT658, R659, R660, R661 and R662 connect the Mx, x=0 to 6, signals from connectors J601, J602, J603, J604, J605, J606 and J607 to U602 level shifter. Unsolder them when the Mx pins are used as auxiliary references and a clean path towards the AD9546 is necessary.
The AD9546 evaluation board is supported by Windows® based software that allows the user to access all the functionality of the AD9546. The software communicates with the board using the USB. On the evaluation board, the CY7C68013A USB microcontroller then communicates with the AD9546 to process the requests that are sent from the PC. The evaluation software uses only the 3-wire SPI communication to communicate with the AD9546. The 4-wire SPI and I2C communications are not supported.
Download the AD9546 Evaluation Software from the AD9546 Evaluation Board Website, unzip it and run the executable.
The AD9546 evaluation board does not need to be connected to the PC to install the evaluation software.
Connect a USB cable between the PC and the AD9546 evaluation board. Power up the board by connecting the 6V wall supply provided with the evaluation kit. The Windows® Device manager recognizes the board as the ADI Evaluation System (Figure 1):
Figure 1: AD9546 Evaluation Board Connected to the PC – as it appears in Windows Device Manager
Figure 2: AD9546 Evaluation Software Front Panel
Click on File menu at the top left of the front panel and the following entries are available:
Figure 3: Select Hardware Entry in File dialog
Multiple AD9546 Evaluation Boards may be connected simultaneously to the same PC. Figure 3b shows the Select Hardware dialog when two boards are connected to the same PC. Proceed in the following way to use two instances of the AD9546 Evaluation Software.
Proceed the same if other AD9546 evaluation boards must be used.
Do not unplug or power down one or more boards already selected in the Select Hardware dialog.
Figure 3b: Select Hardware dialog window when Two AD9546 Evaluation Boards are Connected to the same PC
Click on View menu on the top of the screen and the following entries are available:
Figure 4: Register Map Window
Click on Register Details arrow on the bottom left of the window (Figure 5 below) and the bit content of the particular selected register is displayed. Move the cursor on top of a register and the bit description of that register is visualized.
Figure 5: Register Details section of Register Map Window
Figure 6: Debug Window with Register Selection Scroll Down Menu
Click on Help menu on the top of the front panel (Figure 1) and the following entries are available:
The front panel has two tabs, (Figure 6b): Block Diagram and Pinout.
The Block Diagram provides a user interface to configure all of the AD9546 registers.
The Pinout provides the list of all the AD9546 pins, their position on the package and their description.
Figure 6b: Front Panel's Block Diagram and Pinout tabs
Figure 6c: Front Panel Buttons
Figure 7: Control Window
Figure 8: Status Window
By default, every time the AD9546 Evaluation Software is launched, the Frequency Configuration Wizard is opened. If an AD9546 configuration json file was already created, close the wizard by clicking on the x button on the top right corner of the window and load the file going into File, Configuration Files, Load Configuration File menu (Figure 2). While using the Evaluation Software, the wizard can be launched by clicking on the tab Wizard on the bottom of the front panel (Figure 6c).
Figure 9: Frequency Configuration Wizard Window
The wizard contains several tabs: System Clock, Input Sources, Channel 0 and Channel 1. Short explanations of each tab:
Once all this data is introduced, click Load button on the bottom right of the window for the Wizard to calculate the registers values and load them into the AD9546. The Wizard then closes automatically.
Figure 10: Input Sources Tab of the Frequency Configuration Wizard
Figure 11: Channel 0 Tab of the Frequency Configuration Wizard
Figure 12: Input Source Settings Window
In this window, virtually all the functionality related to the reference clocks can be configured. Click Load to download the register values that have been changed from the evaluation software into the AD9546 and if the Enable IO Update option is enabled in the Options entry in the File menu, an IO Update is executed automatically at the end of the registers download. Also, the window visualizes all the status flags related to the reference that is selected in the window. For example, in Figure 12, the REFA settings are selected. The status flags associated with REFA are also updated in the right side of the window.
Figure 13: Digitized Clocking Settings Window
In this window, the Digitized Clocking settings regarding the common clock, the user time stampers and the inverse user time stampers can be introduced.
Figure 14: System Clock Stability Compensation Settings Window
In this window, the system clock stability compensation methods can be selected and configured.
Figure 15: Multi-Function Pins Settings Window
Figure 16: M-pins by Function Tab Window
In the Front Panel (Figure 2), clicking on IRQ tab launches the window in Figure 17. In this window, every AD9546 interrupt can be enabled or cleared and their trigger status (set or cleared) is visualized. The Group Clear tab provides access to control bits that clear groups of interrupts, that is the bits 3:0 in register 0x2005 (Figure 18).
Figure 17: Interrupt Requests (IRQs) Settings Window
Figure 18: Group Clear Window
Figure 19: Temperature Settings Window
Move the cursor over the white locations for their description. The Compensation section has three entries:
Figure 20: EEPROM Controls Window
This window cannot be used with the AD9546 evaluation board because the board does not contain a EEPROM usable to store the AD9546 configuration.
Figure 21: Channel 0 Settings Window
In this window, all DPLL0 settings can be managed. It is recommended to use the Wizard first to configure the DPLL0 and use this window for additional settings not already set by the Wizard. Click on the DPLL Settings, APLL Settings, DIST (Distribution) Settings tabs on the bottom of the window to access them. Click on Status tab to access the Channel 0 Status window (Figure 22) in which the status flags related to Channel 0 DPLL0+APLL0 are updated. DPLL Settings, APLL Settings and Distribution Settings windows are presented in Figure 23, Figure 24, Figure 25.
Figure 22: Channel 0 Status Window
Figure 23: DPLL0 Settings Window
Figure 24: APLL0 Settings Window
Figure 25: Channel 0 Distribution Settings
In the Front Panel (Figure 2), clicking on Channel 1 section launches a window identical with the Channel 0 Settings window (Figure 21). Use Channel 0 Settings section for more information.