SNLA452 August   2025 DP83TD510E

 

  1.   1
  2.   Abstract
  3.   Trademarks
  4. 1Introduction
  5. 2Troubleshooting the Application
    1. 2.1 Schematic and Layout Checklist
    2. 2.2 Component Checklist
    3. 2.3 Device Health Checks
      1. 2.3.1 Check Voltage Supply Pins
      2. 2.3.2 Probe the RST_N Pin
      3. 2.3.3 Probe the CLKOUT Pin
      4. 2.3.4 Probe the SMI Pins
    4. 2.4 Read and Check Register Values
    5. 2.5 Verifying Strap Configuration
    6. 2.6 Loopbacks
    7. 2.7 MDI Health Checks
      1. 2.7.1 Link Up Common Issues
      2. 2.7.2 Transmit Level
        1. 2.7.2.1 Change Transmit Level
      3. 2.7.3 Time-Domain Reflectometry
      4. 2.7.4 Signal Quality Check
      5. 2.7.5 MDI Test Modes
    8. 2.8 MII Health Checks
      1. 2.8.1 RGMII
      2. 2.8.2 RMII
      3. 2.8.3 MII
  6. 3Summary
  7. 4References

2.3.2 Probe the RST_N Pin

The RST_N pin is an active low input to the PHY. Confirm that the controller is not driving the RST_N signal low, otherwise, the device can be held in reset and can appear non-functional. In this case, the device cannot link up, or even have register access. Make sure that the voltage on this pin corresponds to the chosen VDDIO voltage.