SNLS779A July   2025  – November 2025 DP83TC815-Q1

PRODUCTION DATA  

  1.   1
  2. 1 Features
  3. 2 Applications
  4. 3 Description
  5. 4 Device Comparison Table
  6. 5 Pin Configuration and Functions
    1. 5.1 Pin Power Domain
    2. 5.2 Pin States
    3. 5.3 Pin Multiplexing
  7. 6 Specifications
    1. 6.1 Absolute Maximum Ratings
    2. 6.2 ESD Ratings
    3. 6.3 Recommended Operating Conditions
    4. 6.4 Thermal Information
    5. 6.5 Electrical Characteristics
    6. 6.6 Timing Requirements
    7. 6.7 Timing Diagrams
    8. 6.8 Typical Characteristics
  8. 7 Detailed Description
    1. 7.1 Overview
    2. 7.2 Functional Block Diagram
    3. 7.3 Feature Description
      1. 7.3.1 IEEE802.1AS Features
        1. 7.3.1.1 PTP Clock Configuration
          1. 7.3.1.1.1 PTP Reference Clock
          2. 7.3.1.1.2 PTP Synchronized Clock (Wall Clock)
            1. 7.3.1.1.2.1 PTP Time Read or Write
            2. 7.3.1.1.2.2 PTP Clock Initialization
            3. 7.3.1.1.2.3 PTP Clock Adjustment
            4. 7.3.1.1.2.4 PTP Clock Output
              1. 7.3.1.1.2.4.1 One Pulse Per Second (PPS) Output
          3. 7.3.1.1.3 PTP Time Registers
        2. 7.3.1.2 Packet Timestamps
          1. 7.3.1.2.1 Transmit (Egress) Packet Parser and Timestamp
          2. 7.3.1.2.2 Receive (ingress) Packet Parser and Timestamp
          3. 7.3.1.2.3 PTP Transmit and Receive Timestamp Registers
        3. 7.3.1.3 Event Triggering and Timestamping
          1. 7.3.1.3.1 Event Triggering (Output)
            1. 7.3.1.3.1.1 Trigger Initialization
          2. 7.3.1.3.2 Event Timestamp (Input)
            1. 7.3.1.3.2.1 Timestamp Storage and Reading
          3. 7.3.1.3.3 Event Capture and Output Trigger Registers
        4. 7.3.1.4 PTP Interrupts
        5. 7.3.1.5 PTP I/O Configuration
      2. 7.3.2 TC10 Sleep Wake-up
        1. 7.3.2.1 Functions of the PHY for TC10 Support
          1. 7.3.2.1.1 Transition from Sleep to Wake-up Mode
            1. 7.3.2.1.1.1 Local Wake Detection
            2. 7.3.2.1.1.2 WUP Transmission and Reception
          2. 7.3.2.1.2 Wake Forwarding
          3. 7.3.2.1.3 Transition to Sleep - Sleep Negotiation
            1. 7.3.2.1.3.1 Sleep Ack
            2. 7.3.2.1.3.2 Sleep Request
            3. 7.3.2.1.3.3 Sleep Silent
            4. 7.3.2.1.3.4 Sleep Fail
            5. 7.3.2.1.3.5 Sleep
            6. 7.3.2.1.3.6 Force Sleep
        2. 7.3.2.2 Power Supply Networks for Sleep Applications
        3. 7.3.2.3 Configuration for Non-TC10 Applications
        4. 7.3.2.4 Miscellaneous Sleep Features
        5. 7.3.2.5 Fast Wake-up
      3. 7.3.3 PPM Monitor
      4. 7.3.4 Clock Dithering
      5. 7.3.5 Output Slew Control
      6. 7.3.6 Diagnostic Tool Kit
        1. 7.3.6.1 Signal Quality Indicator
        2. 7.3.6.2 Electrostatic Discharge Sensing
        3. 7.3.6.3 Time Domain Reflectometry
        4. 7.3.6.4 Voltage Sensing
        5. 7.3.6.5 Temperature Sensing
      7. 7.3.7 BIST and Loopback Modes
        1. 7.3.7.1 Data Generator and Checker
        2. 7.3.7.2 xMII Loopback
        3. 7.3.7.3 PCS Loopback
        4. 7.3.7.4 Digital Loopback
        5. 7.3.7.5 Analog Loopback
        6. 7.3.7.6 Reverse Loopback
      8. 7.3.8 Compliance Test Modes
        1. 7.3.8.1 Test Mode 1
        2. 7.3.8.2 Test Mode 2
        3. 7.3.8.3 Test Mode 4
        4. 7.3.8.4 Test Mode 5
    4. 7.4 Device Functional Modes
      1. 7.4.1 Power Modes
        1. 7.4.1.1 Power Down
        2. 7.4.1.2 Reset
        3. 7.4.1.3 Standby
        4. 7.4.1.4 Normal
        5. 7.4.1.5 Sleep
      2. 7.4.2 Media Dependent Interface
        1. 7.4.2.1 100BASE-T1 Leader and 100BASE-T1 Follower Configuration
        2. 7.4.2.2 Auto-Polarity Detection and Correction
        3. 7.4.2.3 Jabber Detection
        4. 7.4.2.4 Interleave Detection
      3. 7.4.3 MAC Interfaces
        1. 7.4.3.1 Media Independent Interface
        2. 7.4.3.2 Reduced Media Independent Interface
        3. 7.4.3.3 Reduced Gigabit Media Independent Interface
        4. 7.4.3.4 Serial Gigabit Media Independent Interface
      4. 7.4.4 Serial Management Interface
        1. 7.4.4.1 Extended Register Space Access
        2. 7.4.4.2 Write Operation (No Post Increment)
        3. 7.4.4.3 Read Operation (No Post Increment)
        4. 7.4.4.4 Write Operation (Post Increment)
        5. 7.4.4.5 Read Operation (Post Increment)
    5. 7.5 Programming
      1. 7.5.1 Strap Configuration
        1. 7.5.1.1 LED Configuration
  9. 8 Register Maps
    1. 8.1 Register Access Summary
    2. 8.2 DP83TC815 Registers
  10. 9 Application and Implementation
    1. 9.1 Application Information
    2. 9.2 Typical Applications
      1. 9.2.1 Design Requirements
        1. 9.2.1.1 Physical Medium Attachment
          1. 9.2.1.1.1 Common-Mode Choke Recommendations
      2. 9.2.2 Detailed Design Procedure
      3. 9.2.3 Application Curves
    3. 9.3 Power Supply Recommendations
    4. 9.4 Layout
      1. 9.4.1 Layout Guidelines
        1. 9.4.1.1 Signal Traces
        2. 9.4.1.2 Return Path
        3. 9.4.1.3 Metal Pour
        4. 9.4.1.4 PCB Layer Stacking
      2. 9.4.2 Layout Example
  11. 10Device and Documentation Support
    1. 10.1 Device Support
      1. 10.1.1 Third-Party Products Disclaimer
    2. 10.2 Receiving Notification of Documentation Updates
    3. 10.3 Support Resources
    4. 10.4 Trademarks
    5. 10.5 Electrostatic Discharge Caution
    6. 10.6 Glossary
  12. 11Revision History
  13. 12Mechanical, Packaging, and Orderable Information

7.3.6.1 Signal Quality Indicator

When the DP83TC815-Q1 is active, the Signal Quality Indicator can be used to determine the quality of link based on SNR readings made by the device. SQI is presented as a 8-level indication. Signal quality indication is accessible through register 0x871. SQI is continuously monitored by the PHY to allow for real-time link signal quality status.

Bits[3:1] in register 0x871 provide SQI value while bits [7:5] provide the worst SQI value since the last read. The SQI value reported in register 0x871[3:1] map directly to the SQI levels required by Open Alliance.

Table 7-16 Signal Quality Indicator
REG 0x871[3:1]OPEN ALLIANCE SQI LEVELLINK QUALITY
0x00 (Worst)Poor/ No Link
0x11
0x22
0x33
0x44Good / Excellent Link
0x55
0x66
0x77 (Best)