SNLS604E September   2020  – November 2022 DP83TG720S-Q1

PRODUCTION DATA  

  1. 1 Features
  2. 2 Applications
  3. 3 Description
  4. 4 Revision History
  5. 5 Pin Configuration and Functions
    1.     Pin Functions
    2. 5.1 Pin States
    3. 5.2 Pin Power Domain
  6. 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 LED Drive Characteristics
  7. 7 Detailed Description
    1. 7.1 Overview
    2. 7.2 Functional Block Diagram
    3. 7.3 Feature Description
      1. 7.3.1 Diagnostic Tool Kit
        1. 7.3.1.1 Signal Quality Indicator
        2. 7.3.1.2 Time Domain Reflectometry
        3. 7.3.1.3 Built-In Self-Test For Datapath
          1. 7.3.1.3.1 Loopback Modes
          2. 7.3.1.3.2 Data Generator
          3. 7.3.1.3.3 Programming Datapath BIST
        4. 7.3.1.4 Temperature and Voltage Sensing
        5. 7.3.1.5 Electrostatic Discharge Sensing
      2. 7.3.2 Compliance Test Modes
        1. 7.3.2.1 Test Mode 1
        2. 7.3.2.2 Test Mode 2
        3. 7.3.2.3 Test Mode 4
        4. 7.3.2.4 Test Mode 5
        5. 7.3.2.5 Test Mode 6
        6. 7.3.2.6 Test Mode 7
    4. 7.4 Device Functional Modes
      1. 7.4.1  Power Down
      2. 7.4.2  Reset
      3. 7.4.3  Standby
      4. 7.4.4  Normal
      5. 7.4.5  Sleep
      6. 7.4.6  State Transitions
        1. 7.4.6.1 State Transition #1 - Standby to Normal
        2. 7.4.6.2 State Transition #2 - Normal to Standby
        3. 7.4.6.3 State Transition #3 - Normal to Sleep
        4. 7.4.6.4 State Transition #4 - Sleep to Normal
      7. 7.4.7  Media Dependent Interface
        1. 7.4.7.1 MDI Master and MDI Slave Configuration
        2. 7.4.7.2 Auto-Polarity Detection and Correction
      8. 7.4.8  MAC Interfaces
        1. 7.4.8.1 Reduced Gigabit Media Independent Interface
        2. 7.4.8.2 Serial Gigabit Media Independent Interface
      9. 7.4.9  Serial Management Interface
      10. 7.4.10 Direct Register Access
      11. 7.4.11 Extended Register Space Access
      12. 7.4.12 Write Address Operation
        1. 7.4.12.1 Example - Write Address Operation
      13. 7.4.13 Read Address Operation
        1. 7.4.13.1 Example - Read Address Operation
      14. 7.4.14 Write Operation (No Post Increment)
        1. 7.4.14.1 Example - Write Operation (No Post Increment)
      15. 7.4.15 Read Operation (No Post Increment)
        1. 7.4.15.1 Example - Read Operation (No Post Increment)
      16. 7.4.16 Write Operation (Post Increment)
        1. 7.4.16.1 Example - Write Operation (Post Increment)
      17. 7.4.17 Read Operation (Post Increment)
        1. 7.4.17.1 Example - Read Operation (Post Increment)
    5. 7.5 Programming
      1. 7.5.1 Strap Configuration
      2. 7.5.2 LED Configuration
      3. 7.5.3 PHY Address Configuration
    6. 7.6 Register Maps
      1. 7.6.1 Register Access Summary
      2. 7.6.2 DP83TG720 Registers
        1. 7.6.2.1 Base Registers
  8. 8 Application and Implementation
    1. 8.1 Application Information
    2. 8.2 Typical Applications
  9. 9 Power Supply Recommendations
  10. 10Compatibility with TI's 100BT1 PHY
  11. 11Layout
    1. 11.1 Layout Guidelines
      1. 11.1.1 Signal Traces
      2. 11.1.2 Return Path
      3. 11.1.3 Physical Medium Attachment
      4. 11.1.4 Metal Pour
      5. 11.1.5 PCB Layer Stacking
  12. 12Device and Documentation Support
    1. 12.1 Receiving Notification of Documentation Updates
    2. 12.2 Support Resources
    3. 12.3 Trademarks
    4. 12.4 Electrostatic Discharge Caution
    5. 12.5 Glossary
  13. 13Mechanical, Packaging, and Orderable Information
    1. 13.1 Package Option Addendum
      1. 13.1.1 Packaging Information
      2. 13.1.2 Tape and Reel Information

Package Options

Mechanical Data (Package|Pins)
Thermal pad, mechanical data (Package|Pins)
Orderable Information

7.4.8.2 Serial Gigabit Media Independent Interface

The Serial Gigabit Media Independent Interface (SGMII) provides a means for data transfer between MAC and PHY with significantly less signal pins (4 pins) compared to RGMII (12 pins). SGMII uses low-voltage differential signaling (LVDS) to reduce emissions and improve signal quality.

The DP83TG720S-Q1 SGMII is capable of operating in 4-wire mode. In 4-wire operation, two differential pairs are used to transmit and receive data. Clock and data recovery are performed in the MAC and in the PHY in the case of the RX and TX directions, respectively.

SGMII Auto-Negotitation can be disabled by setting bit[0] = 0b0 in the SGMII Configuration Register (SGMIICTL, address 0x608).

The SGMII signals are summarized in Table 7-13.

Table 7-13 SGMII Signals
FUNCTIONPINS
Data SignalsTX_M, TX_P
RX_M, RX_P
GUID-8593B570-2230-45AD-A33A-91B06171D51F-low.gifFigure 7-16 SGMII Connections

SGMII MAC Interface for Gigabit Ethernet has stringent signal integrity requirements to meet system level performance. It is advised to take the following requirements into consideration when designing PCB. It is also recommended to check board level signal integrity by using the DP83TG720 IBIS model.

SGMII Signals Guidelines

  • Sgmii Tx and Rx signals should be routed on board with control differential impedance of 100ohms +/- 5%.
  • Maximum routing length should be limited to 5inch for better signal integrity.
  • Mismatch in routing length of p and n should be limited to 5mils.
  • AC-coupling caps on rx lines should be placed close to rx_p and rx_m pins of PHY.
  • AC-coupling caps on tx lines should be placed close to tx_p and tx_m pins of MAC.
  • Signal integrity should be checked only at the pins of the receiver (PHY or MAC) using the high speed differential probe.
  • At PHY's TX_M and TX_P following eye mask should be ensured :

    GUID-56BD60EA-8079-4868-A73C-7AE424388050-low.gif Figure 7-17 Sgmii PHY Receiver Mask Requirement