SNAU297 July   2025 LMK5B12212 , LMK5C22212A

 

  1.   1
  2.   Description
  3.   Features
  4.   4
  5. 1Evaluation Module Overview
    1. 1.1 Introduction
    2. 1.2 Kit Contents
    3. 1.3 Specification
    4. 1.4 Device Information
    5. 1.5 Using LMK5B12212EVM to evaluate LMK5C22212A
  6. 2Hardware
    1. 2.1 Test Equipment Recommended
    2. 2.2 LMK5B12212EVM Default Settings
    3. 2.3 EVM Quick Start
  7. 3Software
    1. 3.1 Getting Started With TICS Pro
    2. 3.2 Programming the LMK5B12212
    3. 3.3 Configuring TICS Pro
      1. 3.3.1  Using the Start Page
        1. 3.3.1.1 Step 1
        2. 3.3.1.2 Step 2
        3. 3.3.1.3 Step 3
        4. 3.3.1.4 Step 4
        5. 3.3.1.5 Step 5
        6. 3.3.1.6 Step 6
        7. 3.3.1.7 Step 7
        8. 3.3.1.8 Step 8
      2. 3.3.2  Using the Status Page
      3. 3.3.3  Using the Input Page
        1. 3.3.3.1 Cascaded Configurations
          1. 3.3.3.1.1 Cascade VCO to APLL Reference
      4. 3.3.4  Using APLLx Pages
        1. 3.3.4.1 APLL DCO
      5. 3.3.5  Using the DPLLx Page
        1. 3.3.5.1 DPLL DCO
      6. 3.3.6  Using the Validation Page
      7. 3.3.7  Using the GPIO Page
        1. 3.3.7.1 SYNC/SYSREF/1-PPS Page
      8. 3.3.8  Using the Outputs Page
      9. 3.3.9  EEPROM Page
      10. 3.3.10 Design Report Page
  8. 4EVM Configuration
    1. 4.1 Evaluation Setup
      1. 4.1.1 Power Supply
      2. 4.1.2 Logic Inputs and Outputs
      3. 4.1.3 Switching Between I2C and SPI
      4. 4.1.4 Generating SYSREF Request
      5. 4.1.5 XO Input
        1. 4.1.5.1 48MHz TCXO (Default)
        2. 4.1.5.2 External Clock Input
        3. 4.1.5.3 Additional XO Input Options
        4. 4.1.5.4 APLL Reference Options
      6. 4.1.6 Reference Clock Inputs
      7. 4.1.7 Clock Outputs
      8. 4.1.8 Status Outputs and LEDS
      9. 4.1.9 Requirements for Making Measurements
    2. 4.2 Typical Phase Noise Characteristics
  9. 5Hardware Design Files
    1. 5.1 Schematics
      1. 5.1.1  Power Supply Schematic
      2. 5.1.2  Alternative Power Supply Schematic
      3. 5.1.3  Power Distribution Schematic
      4. 5.1.4  LMK5B12212 and Input References IN0 to IN1 Schematic
      5. 5.1.5  Clock Outputs OUT0 to OUT3 Schematic
      6. 5.1.6  Clock Outputs OUT4 to OUT7 Schematic
      7. 5.1.7  Clock Outputs OUT8 to OUT11 Schematic
      8. 5.1.8  XO Schematic
      9. 5.1.9  Logic I/O Interfaces Schematic
      10. 5.1.10 USB2ANY Schematic
    2. 5.2 PCB Layouts
      1. 5.2.1 Layout Guidelines
      2. 5.2.2 Layout Example
      3. 5.2.3 Thermal Reliability
    3. 5.3 Bill of Materials (BOM)
      1. 5.3.1 Loop Filter and Vibration Nonsensitive Capacitors

4.1.4 Generating SYSREF Request

A software request, 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 is dedicated for SPI readback. In 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.

LMK5B12212EVM GPIO Setting for SYSREF RequestFigure 4-7 GPIO Setting for SYSREF Request
LMK5B12212EVM GPIO Pin Selection for SYSREFFigure 4-8 GPIO Pin Selection for SYSREF