SNLS505G july   2016  – august 2023 DP83822H , DP83822HF , DP83822I , DP83822IF

PRODUCTION DATA  

  1.   1
  2. 1 Features
  3. 2 Applications
  4. 3 Description
  5. 4 Revision History
  6. 5 Device Comparison Table
  7. 6 Pin Configuration and Functions
  8. 7 Specifications
    1. 7.1  Absolute Maximum Ratings
    2. 7.2  ESD Ratings
    3. 7.3  Recommended Operating Conditions
    4. 7.4  Thermal Information
    5. 7.5  Electrical Characteristics
    6. 7.6  Timing Requirements, Power-Up Timing
    7. 7.7  Timing Requirements, Power-Up With Unstable XI Clock
    8. 7.8  Timing Requirements, Reset Timing
    9. 7.9  Timing Requirements, Serial Management Timing
    10. 7.10 Timing Requirements, 100 Mbps MII Transmit Timing
    11. 7.11 Timing Requirements, 100 Mbps MII Receive Timing
    12. 7.12 Timing Requirements, 10 Mbps MII Transmit Timing
    13. 7.13 Timing Requirements, 10 Mbps MII Receive Timing
    14. 7.14 Timing Requirements, RMII Transmit Timing
    15. 7.15 Timing Requirements, RMII Receive Timing
    16. 7.16 Timing Requirements, RGMII
    17. 7.17 Normal Link Pulse Timing
    18. 7.18 Auto-Negotiation Fast Link Pulse (FLP) Timing
    19. 7.19 10BASE-Te Jabber Timing
    20. 7.20 100BASE-TX Transmit Latency Timing
    21. 7.21 100BASE-TX Receive Latency Timing
    22. 7.22 Timing Diagrams
    23. 7.23 Typical Characteristics
  9. 8 Detailed Description
    1. 8.1 Overview
    2. 8.2 Functional Block Diagram
    3. 8.3 Feature Description
      1. 8.3.1 Energy Efficient Ethernet
        1. 8.3.1.1 EEE Overview
        2. 8.3.1.2 EEE Negotiation
      2. 8.3.2 Wake-on-LAN Packet Detection
        1. 8.3.2.1 Magic Packet Structure
        2. 8.3.2.2 Magic Packet Example
        3. 8.3.2.3 Wake-on-LAN Configuration and Status
      3. 8.3.3 Start of Frame Detect for IEEE 1588 Time Stamp
      4. 8.3.4 Clock Output
    4. 8.4 Device Functional Modes
      1. 8.4.1  MAC Interfaces
        1. 8.4.1.1 Media Independent Interface (MII)
        2. 8.4.1.2 Reduced Media Independent Interface (RMII)
        3. 8.4.1.3 Reduced Gigabit Media Independent Interface (RGMII)
      2. 8.4.2  Serial Management Interface
        1. 8.4.2.1 Extended Register Space Access
        2. 8.4.2.2 Write Address Operation
        3. 8.4.2.3 Read Address Operation
        4. 8.4.2.4 Write (No Post Increment) Operation
        5. 8.4.2.5 Read (No Post Increment) Operation
        6. 8.4.2.6 Write (Post Increment) Operation
        7. 8.4.2.7 Read (Post Increment) Operation
        8. 8.4.2.8 Example Write Operation (No Post Increment)
        9. 8.4.2.9 Example Read Operation (No Post Increment)
      3. 8.4.3  100BASE-TX
        1. 8.4.3.1 100BASE-TX Transmitter
          1. 8.4.3.1.1 Code-Group Encoding and Injection
          2. 8.4.3.1.2 Scrambler
          3. 8.4.3.1.3 NRZ to NRZI Encoder
          4. 8.4.3.1.4 Binary to MLT-3 Converter
        2. 8.4.3.2 100BASE-TX Receiver
      4. 8.4.4  100BASE-FX
        1. 8.4.4.1 100BASE-FX Transmit
        2. 8.4.4.2 100BASE-FX Receive
      5. 8.4.5  10BASE-Te
        1. 8.4.5.1 Squelch
        2. 8.4.5.2 Normal Link Pulse Detection and Generation
        3. 8.4.5.3 Jabber
        4. 8.4.5.4 Active Link Polarity Detection and Correction
      6. 8.4.6  Auto-Negotiation (Speed / Duplex Selection)
      7. 8.4.7  Auto-MDIX Resolution
      8. 8.4.8  Loopback Modes
        1. 8.4.8.1 Near-End Loopback
        2. 8.4.8.2 MII Loopback
        3. 8.4.8.3 PCS Loopback
        4. 8.4.8.4 Digital Loopback
        5. 8.4.8.5 Analog Loopback
        6. 8.4.8.6 Far-End (Reverse) Loopback
      9. 8.4.9  BIST Configurations
      10. 8.4.10 Cable Diagnostics
        1. 8.4.10.1 TDR
      11. 8.4.11 Fast Link Down Functionality
    5. 8.5 Programming
      1. 8.5.1 Hardware Bootstrap Configurations
      2. 8.5.2 LED Configuration
      3. 8.5.3 PHY Address Configuration
    6. 8.6 Register Maps
  10. 9 Application and Implementation
    1. 9.1 Application Information
    2. 9.2 Typical Applications
      1. 9.2.1 TPI Network Circuit
        1. 9.2.1.1 Design Requirements
        2. 9.2.1.2 Detailed Design Procedure
        3. 9.2.1.3 Application Curves
      2. 9.2.2 Fiber Network Circuit
        1. 9.2.2.1 Design Requirements
          1. 9.2.2.1.1 Clock Requirements
            1. 9.2.2.1.1.1 Oscillator
            2. 9.2.2.1.1.2 Crystal
        2. 9.2.2.2 Detailed Design Procedure
          1. 9.2.2.2.1 MII Layout Guidelines
          2. 9.2.2.2.2 RMII Layout Guidelines
          3. 9.2.2.2.3 RGMII Layout Guidelines
          4. 9.2.2.2.4 MDI Layout Guidelines
        3. 9.2.2.3 Application Curves
  11. 10Power Supply Recommendations
    1. 10.1 Power Supply Characteristics
  12. 11Layout
    1. 11.1 Layout Guidelines
      1. 11.1.1 Signal Traces
      2. 11.1.2 Return Path
      3. 11.1.3 Transformer Layout
        1. 11.1.3.1 Transformer Recommendations
      4. 11.1.4 Metal Pour
      5. 11.1.5 PCB Layer Stacking
    2. 11.2 Layout Example
  13. 12Device and Documentation Support
    1. 12.1 Related Links
    2. 12.2 Receiving Notification of Documentation Updates
    3. 12.3 Support Resources
    4. 12.4 Trademarks
    5. 12.5 Electrostatic Discharge Caution
    6. 12.6 Glossary
  14. 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

8.4.11 Fast Link Down Functionality

The DP83822 includes advanced link-down capabilities that support various real-time applications. The link-down mechanism is configurable and includes enhanced modes that allow extremely fast link-drop reaction times.

The DP83822 supports an enhanced link drop mechanism, also called Fast Link Drop (FLD), which shortens the observation window for determining link. There are multiple ways of determining link status, which can be enabled or disabled based on user preference. Fast Link Drop can be enabled in hardware with bootstrapping or in software using register configuration. RX_D2 when strapped to either mode 2 or mode 3 will enable FLD at power up or hardware reset. Additionally, FLD can be configured using the Control Register #3 (CR3, address 0x000B). Bits[3:0] and bit[10] allow for various FLD conditions to be enabled. When link drop occurs, indication of a particular fault condition can be read from the Fast Link Down Status Register (FLDS, address 0x000F).

GUID-F4990690-DBC4-4B75-B5CB-331737E61497-low.gifFigure 8-9 Fast Link Down

Fast Link Down criteria include:

  • RX Error Count - when a predefined number of 32 RX_ERs occur in a 10μs window, the link will be dropped.
  • MLT3 Error Count - when a predefined number of 20 MLT3 errors occur in a 10μs window, the link will be dropped.
  • Low SNR Threshold - when a predefined number of 20 threshold crossings occur in a 10μs window, the link will be dropped.
  • Signal/Energy Loss - when the energy detector indicates energy loss, the link will be dropped.

The Fast Link Down functionality allows the use of each of these options separately or in any combination.

Note:

Because this mode enables extremely quick reaction time, it is more exposed to temporary bad link-quality scenarios.