Texas Instruments SCAU020 manual ChronosGUI, Using Software-Enabled Automatic PLL Selection

Page 9

www.ti.com

ChronosGUI

After the setup wizard completes, start the GUI interface from the Start menu (StartTexas InstrumentsChronos EvalTIChronosGUI.exe).

Connect the USB cable to the EVM. If Microsoft Windows prompts you for an appropriate driver, do not use the automatic search option. Select a manual installation. When prompted for the driver location, browse to the Chronos GUI file folder that was created during installation. (If the operating system does not ask for a driver, no additional action is needed.)

Once the USB driver installation completes, the GUI software should connect properly and be ready for use. A green light in the USB communication box indicates a good USB connection; a red light indicates a faulty USB connection. If the connection is not established, attempt to re-install the drivers.

6ChronosGUI

Figure 5 shows the Chronos GUI used to navigate the EVM software.

Figure 5. TI Chronos Software GUI

6.1Using Software-Enabled Automatic PLL Selection

The software illustration Figure 5 shows the on-chip PLL structure of the CDCE421. Through this screen, the user can change the Input Frequency, PFD Charge Pump, Loop Filter, and Output Type. The other features are selected by the software; user-selectable options are described in this section.

Step 1. IC Block Configuration and Input Calculator.

Before programming the PLL, the specific EVM block that is being programmed must be selected in the IC Block Config section of the GUI. For any block in the EVM being used, the first row of calculations is useful when trying to investigate the input frequency to the CDCE421 needed to obtain a desired output frequency. The input frequency is obtained by pressing the Calculate button.

Step 2. Store Crystal Frequency.

If a crystal input is used for Block B of the EVM, the crystal frequency must be entered into the space provided; click on the Device_EEPROM drop-down menu at the top of the software GUI. A menu item labeled Save Block B–XTAL Freq to EEPROM appears; this menu item must be selected. The crystal

SCAU020 –March 2007

10.9MHz–1175MHz Low Phase Noise Clock Evaluation Board

9

Image 9
Contents Users Guide Submit Documentation Feedback Contents List of Figures General Description CDCE421EVM Evaluation Board FeaturesCDCE421EVM Programming Blocks Signal Path and Control CircuitryBlock B Block aBlock C Block DSoftware Installation Screen Installing the Software GUI and USB DriverIC Block Configuration and Input Calculator Using Software-Enabled Automatic PLL SelectionChronosGUI Store Crystal FrequencyOutput Calculator and Apply PLL Settings PLL Bandwidth SelectWrite to CDCE421 Eeprom Chronos GUI-Manual PLL Block Selection Pop-Up Manual PLL Block Selection Advanced ControlSection Function Software Settings DescriptionProgramming Configuration USB Cable Attached Configuring the BoardCDCE421EVM Block Switch Off Schematics and LayoutCDCE421EVM Board Schematic CDCE421EVM Board-Block a Schematic CDCE421EVM Board-Block B Schematic CDCE421EVM Board-Block C Schematic CDCE421EVM Board-Block D Schematic FCC Warning Evaluation BOARD/KIT Important NoticeImportant Notice