SNLS647G december   2019  – july 2023 DP83826E , DP83826I

PRODUCTION DATA  

  1.   1
  2. Features
  3. Applications
  4. Description
  5. Revision History
  6. Mode Comparison Tables
  7. Pin Configuration and Functions (ENHANCED Mode)
  8. Pin Configuration and Functions (BASIC Mode)
  9. Specifications
    1. 8.1 Absolute Maximum Ratings
    2. 8.2 ESD Ratings
    3. 8.3 Recommended Operating Conditions
    4. 8.4 Thermal Information
    5. 8.5 Electrical Characteristics
    6. 8.6 Timing Requirements
    7. 8.7 Timing Diagrams
    8. 8.8 Typical Characteristics
  10. Detailed Description
    1. 9.1 Overview
    2. 9.2 Functional Block Diagram
    3. 9.3 Feature Description
      1. 9.3.1  Auto-Negotiation (Speed/Duplex Selection)
      2. 9.3.2  Auto-MDIX Resolution
      3. 9.3.3  Energy Efficient Ethernet
        1. 9.3.3.1 EEE Overview
        2. 9.3.3.2 EEE Negotiation
      4. 9.3.4  EEE for Legacy MACs Not Supporting 802.3az
      5. 9.3.5  Wake-on-LAN Packet Detection
        1. 9.3.5.1 Magic Packet Structure
        2. 9.3.5.2 Magic Packet Example
        3. 9.3.5.3 Wake-on-LAN Configuration and Status
      6. 9.3.6  Low Power Modes
        1. 9.3.6.1 Active Sleep
        2. 9.3.6.2 IEEE Power-Down
        3. 9.3.6.3 Deep Power Down State
      7. 9.3.7  RMII Repeater Mode
      8. 9.3.8  Clock Output
      9. 9.3.9  Media Independent Interface (MII)
      10. 9.3.10 Reduced Media Independent Interface (RMII)
      11. 9.3.11 Serial Management Interface
        1. 9.3.11.1 Extended Register Space Access
        2. 9.3.11.2 Write Address Operation
        3. 9.3.11.3 Read Address Operation
        4. 9.3.11.4 Write (No Post Increment) Operation
        5. 9.3.11.5 Read (No Post Increment) Operation
        6. 9.3.11.6 Example Write Operation (No Post Increment)
      12. 9.3.12 100BASE-TX
        1. 9.3.12.1 100BASE-TX Transmitter
          1. 9.3.12.1.1 Code-Group Encoding and Injection
          2. 9.3.12.1.2 Scrambler
          3. 9.3.12.1.3 NRZ to NRZI Encoder
          4. 9.3.12.1.4 Binary to MLT-3 Converter
        2. 9.3.12.2 100BASE-TX Receiver
      13. 9.3.13 10BASE-Te
        1. 9.3.13.1 Squelch
        2. 9.3.13.2 Normal Link Pulse Detection and Generation
        3. 9.3.13.3 Jabber
        4. 9.3.13.4 Active Link Polarity Detection and Correction
      14. 9.3.14 Loopback Modes
        1. 9.3.14.1 Near-end Loopback
        2. 9.3.14.2 MII Loopback
        3. 9.3.14.3 PCS Loopback
        4. 9.3.14.4 Digital Loopback
        5. 9.3.14.5 Analog Loopback
        6. 9.3.14.6 Far-End (Reverse) Loopback
      15. 9.3.15 BIST Configurations
      16. 9.3.16 Cable Diagnostics
        1. 9.3.16.1 Time Domain Reflectometry (TDR)
        2. 9.3.16.2 Fast Link-Drop Functionality
      17. 9.3.17 LED and GPIO Configuration
    4. 9.4 Programming
      1. 9.4.1 Hardware Bootstraps Configuration
        1. 9.4.1.1 DP83826 Bootstrap Configurations (ENHANCED Mode)
          1. 9.4.1.1.1 Bootstraps for PHY Address
        2. 9.4.1.2 DP83826 Strap Configuration (BASIC Mode)
          1. 9.4.1.2.1 Bootstraps for PHY Address
    5. 9.5 Register Maps
      1. 9.5.1 DP83826 Registers
  11. 10Application and Implementation
    1. 10.1 Application Information
    2. 10.2 Typical Applications
      1. 10.2.1 Twisted-Pair Interface (TPI) Network Circuit
      2. 10.2.2 Transformer Recommendations
      3. 10.2.3 Capacitive DC Blocking
      4. 10.2.4 Design Requirements
        1. 10.2.4.1 Clock Requirements
          1. 10.2.4.1.1 Oscillator
          2. 10.2.4.1.2 Crystal
      5. 10.2.5 Detailed Design Procedure
        1. 10.2.5.1 MII Layout Guidelines
        2. 10.2.5.2 RMII Layout Guidelines
        3. 10.2.5.3 MDI Layout Guidelines
      6. 10.2.6 Application Curves
  12. 11Power Supply Recommendations
  13. 12Layout
    1. 12.1 Layout Guidelines
      1. 12.1.1 Signal Traces
      2. 12.1.2 Return Path
      3. 12.1.3 Transformer Layout
      4. 12.1.4 Metal Pour
      5. 12.1.5 PCB Layer Stacking
        1. 12.1.5.1 Layout Example
  14. 13Device and Documentation Support
    1. 13.1 Related Documentation
    2. 13.2 Receiving Notification of Documentation Updates
    3. 13.3 Support Resources
    4. 13.4 Trademarks
    5. 13.5 Electrostatic Discharge Caution
    6. 13.6 Glossary
  15. 14Mechanical, Packaging, and Orderable Information

Package Options

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

Serial Management Interface

The Serial Management Interface provides access to the DP83826 internal register space for status information and configuration. The SMI is compatible with IEEE 802.3 clause 22. The implemented register set consists of the registers required by the IEEE 802.3 plus several others to provide additional visibility and controllability of the DP83826.

The SMI includes the management clock (MDC) and the management input/output data pin (MDIO). MDC is sourced by the external management entity, also called Station (STA), and can run at a maximum clock rate of 24 MHz. MDC is not expected to be continuous, and can be turned off by the external management entity when the bus is idle.

MDIO is sourced by the external management entity and by the PHY. The data on the MDIO pin is latched on the rising edge of the MDC. MDIO pin requires a pullup resistor (2.2 KΩ or 1.5 KΩ are widely used values), which pulls MDIO high during IDLE and turnaround.

Up to 8 PHYs can share a common SMI bus. To distinguish between the PHYs, during power up or hardware reset, the DP83826 latches the Phy_Address[2:0] configuration pins to determine its address.

The management entity must not start an SMI transaction in the first cycle after power up or hardware reset. To maintain valid operation, the SMI bus must remain inactive at least until 50ms after power-up and at least until 2ms after reset is de-asserted (Refer to T4 in Power-up Timing and T2 in Reset Timing). In normal MDIO transactions, the register address is taken directly from the management-frame reg_addr field, thus allowing direct access to 32 16-bit registers (including those defined in IEEE 802.3 and vendor specific). The data field is used for both reading and writing. The Start code is indicated by a <01> pattern. This pattern makes sure that the MDIO line transitions from the default idle line state. Turnaround is defined as an idle bit time inserted between the Register Address field and the Data field. To avoid contention during a read transaction, no device may actively drive the MDIO signal during the first bit of turnaround. The addressed DP83826 drives the MDIO with a zero for the second bit of turnaround and follows this with the required data.

For write transactions, the station-management entity writes data to the addressed DP83826, thus eliminating the requirement for MDIO Turnaround. The turnaround time is filled by the management entity by inserting <10>.

Table 9-3 SMI Protocol
SMI PROTOCOL<idle><start><op code><PHY address><reg addr><turnaround><data><idle>
Read Operation<idle><01><10><AAAAA><RRRRR><Z0><XXXX XXXX XXXX XXXX><idle>
Write Operation<idle><01><01><AAAAA><RRRRR><10><XXXX XXXX XXXX XXXX><idle>