SNAU246A June   2020  – January 2021 LMX2820

 

  1. 1Trademarks
  2. 2LMX2820EVM Evaluation Module
    1. 2.1 Evaluation Module Contents
    2. 2.2 Evaluation Setup Requirement
    3. 2.3 Resources
  3. 3Setup
    1. 3.1 Connection Diagram
    2. 3.2 Power Supply
    3. 3.3 Reference Clock
    4. 3.4 RF Output
    5. 3.5 Programming
    6. 3.6 Evaluation Software
  4. 4Typical Measurement
    1. 4.1 Default Configuration
      1. 4.1.1 Loop Filter
      2. 4.1.2 Typical Output
    2. 4.2 Additional Tests
      1. 4.2.1 SYSREF Example
      2. 4.2.2 Offset Mixing With PFDIN Pin
      3. 4.2.3 External VCO Mode
      4. 4.2.4 Register Readback
  5. 5Schematic
  6. 6PCB Layout and Layer Stack-Up
    1. 6.1 PCB Layer Stack-Up
    2. 6.2 PCB Layout
  7. 7Bill of Materials
  8. 8Troubleshooting Guide
    1.     A Using Different Reference Clock
      1.      B USB2ANY Firmware Upgrade
        1.       C Revision History

3.3 Reference Clock

Connect the OSCINP SMA connector to a high-quality, 100-MHz signal source. The OSCINN SMA connector can be left open because the OSCIN_N pin is terminated onboard.

The EVM is configured for single-ended input with the OSCIN_P pin connected to the OSCINP SMA connector and the OSCIN_N pin 50-Ω terminated onboard. If required, the EVM can be modified to operate with a different clock source in a different configuration. See Section A for more details.