SNAU296 December   2023 LMK5C33414A

 

  1.   1
  2.   Abstract
  3.   Trademarks
  4. 1Introduction
  5. 2EVM Quick Start
  6. 3EVM Configuration
    1. 3.1  Power Supply
    2. 3.2  Logic Inputs and Outputs
    3. 3.3  Switching Between I2C and SPI
    4. 3.4  Generating SYSREF Request
    5. 3.5  XO Input
      1. 3.5.1 48-MHz TCXO (Default)
      2. 3.5.2 External Clock Input
      3. 3.5.3 Additional XO Input Options
      4. 3.5.4 APLL Reference Options
    6. 3.6  Reference Clock Inputs
    7. 3.7  Clock Outputs
    8. 3.8  Status Outputs and LEDs
    9. 3.9  Requirements for Making Measurements
    10. 3.10 Typical Phase Noise Characteristics
  7. 4EVM Schematics
    1. 4.1  Power Supply Schematic
    2. 4.2  Alternative Power Supply Schematic
    3. 4.3  Power Distribution Schematic
    4. 4.4  LMK5C33414A and Input References IN0 to IN3 Schematic
    5. 4.5  Clock Outputs OUT0 to OUT3 Schematic
    6. 4.6  Clock Outputs OUT4 to OUT9 Schematic
    7. 4.7  Clock Outputs OUT10 to OUT13 and Clock Inputs IN2 and IN3 Schematic
    8. 4.8  XO Schematic
    9. 4.9  Logic I/O Interfaces Schematic
    10. 4.10 USB2ANY Schematic
  8. 5EVM Bill of Materials
    1. 5.1 Loop Filter and Vibration Nonsensitive Capacitors
  9. 6Appendix A - TICS Pro LMK5C33414A Software
    1. 6.1  Using the Start Page
      1. 6.1.1 Step 1
      2. 6.1.2 Step 2
      3. 6.1.3 Step 3
      4. 6.1.4 Step 4
      5. 6.1.5 Step 5
      6. 6.1.6 Step 6
      7. 6.1.7 Step 7
    2. 6.2  Using the Status Page
    3. 6.3  Using the Input Page
      1. 6.3.1 Cascaded Configurations
        1. 6.3.1.1 Cascade VCO to APLL Reference
    4. 6.4  Using APLL1, APLL2, and APLL3 Pages
      1. 6.4.1 APLL DCO
    5. 6.5  Using the DPLL1, DPLL2, and DPLL3 Pages
    6. 6.6  Using the Validation Page
      1. 6.6.1 DPLL DCO
    7. 6.7  Using the GPIO Page
    8. 6.8  SYNC/SYSREF/1-PPS Page
    9. 6.9  Using the Outputs Page
    10. 6.10 EEPROM Page
    11. 6.11 Design Report Page

Generating SYSREF Request

Standard SPI/I2C programming, GPIO0, or GPIO1 can be used to generate a SYSREF request. The TICS Pro software and EVM is designed to use GPIO2 for SPI readback (SDO). Accordingly, GPIO2 is not listed in the pins as GPIO2 is dedicated for SPI readback. In a user application, any GPIO pin can be used.

Connect the desired GPIO pin to the MCU by setting S2 as ON on the switch block for the desired GPIO. Then, make sure the GPIO pin is configured for SYSREF_REQ on the GPIO tab of the GUI. A SYSREF Request can now be issued by toggling the GPIO buttons in the Pins section of the User Controls tab.

GUID-20220610-SS0I-DN94-W6ZM-4VZ0M846FTL4-low.pngFigure 3-7 GPIO Setting for SYSREF Request
GUID-B485E3CC-14DF-4B5F-A792-30FDA39962F5-low.pngFigure 3-8 GPIO Pin Selection for SYSREF