SNLA417 January   2023 DP83TC812R-Q1 , DP83TC812S-Q1

 

  1.   Abstract
  2. 1Introduction
    1. 1.1 Acronyms
  3. 2TC10 Test Setup
    1. 2.1 Overview
    2. 2.2 Wakeup to Linking Sequence
  4. 3Measurement Summary
    1. 3.1 Complete Timing Diagram
    2. 3.2 Measurement Summary
    3. 3.3 LP1 Wake to Linking Time
  5. 4Timing Measurements
    1. 4.1 LP1 WAKE to INH (T1)
    2. 4.2 LP1 INH to WUP (T2)
    3. 4.3 WUP to PHY INH (T3)
    4. 4.4 PHY INH/Buck EN to Buck nRESET (T4)
    5. 4.5 Buck nRESET/PMIC Enable to MCU nReset (T5)
    6. 4.6 MCU nReset to MDIO Communication (T6 and T7)
    7. 4.7 MDIO Master Configuration + Linking (T8 and T9)
  6. 5Measurement Evaluation
    1. 5.1 Recommendations for Optimizing Variable TC10 Times
      1. 5.1.1 Improving MCU Boot-up Time (T6)
      2. 5.1.2 Improving MDIO State Machine (T7)
      3. 5.1.3 Optimizing MDIO Timeline (T8)
        1. 5.1.3.1 Optimizing Master Configuration by Removing Polling
        2. 5.1.3.2 Optimizing Master Configuration by Improving MDC
      4. 5.1.4 PHY Configuration During Sleep
      5. 5.1.5 Other Configurable Values
    2. 5.2 Alternative TC10 Test
  7. 6Conclusion
  8. 7References

1 Introduction

In today’s automotive industry, vehicles – especially electric vehicles (EVs) – are met with the problem of excessive battery consumption from electronic systems. This issue can be mitigated through partial networking using TC10 protocol. TC10 allows Ethernet nodes and their respective electronic control units (ECU) to be disabled when not in use which leads to longer drive range and reduced battery consumption.

The Open Alliance TC10 specification is an automotive Ethernet standard which defines a sleep mode and wake-up mechanism. To learn more about the general TC10 Sleep and Wake Sequence, see the What is the TC10 automotive Ethernet standard and why is it important? video.

This document demonstrates measurements for a complete Ethernet system that utilizes the DP83TC812-Q1, a 100BASE-T1-compliant Ethernet PHY with TC10 sleep and wake functionality. When a sleeping ECU receives a TC10 wake-up pulse (WUP), the ECU must wake and establish the Ethernet link in a reasonable amount of time. Thus, the sleeping ECU can be awakened and perform the requested function with minimal delay. This application note analyzes the steps a TC10 system goes through to wake up and link the Ethernet PHYs as well as detailing any possible optimizations for faster TC10 wake-up times. For more information on the DP83TC812-Q1 PHY configuration for TC10, see the DP83TC812, DP83TC813: System Implementation of Open Alliance TC10 Sleep/Wake-up application note.