SNLS614C September   2018  – April 2024 DP83869HM

PRODUCTION DATA  

  1.   1
  2. 1 Features
  3. 2 Applications
  4. 3 Description
  5. 4 Device Comparison
  6. 5 Pin Configuration and Functions
  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  WoL (Wake-on-LAN) Packet Detection
        1. 7.3.1.1 Magic Packet Structure
        2. 7.3.1.2 Wake-on-LAN Configuration and Status
      2. 7.3.2  Start of Frame Detect for IEEE 1588 Time Stamp
        1. 7.3.2.1 SFD Latency Variation and Determinism
          1. 7.3.2.1.1 1000Mb SFD Variation in Master Mode
          2. 7.3.2.1.2 1000Mb SFD Variation in Slave Mode
          3. 7.3.2.1.3 100-Mb SFD Variation
      3. 7.3.3  Clock Output
      4. 7.3.4  Loopback Mode
        1. 7.3.4.1 Near-End Loopback
          1. 7.3.4.1.1 MII Loopback
          2. 7.3.4.1.2 PCS Loopback
          3. 7.3.4.1.3 Digital Loopback
          4. 7.3.4.1.4 Analog Loopback
          5. 7.3.4.1.5 External Loopback
          6. 7.3.4.1.6 Far-End (Reverse) Loopback
        2.       37
      5. 7.3.5  BIST Configuration
      6. 7.3.6  Interrupt
      7. 7.3.7  Power-Saving Modes
        1. 7.3.7.1 IEEE Power Down
        2. 7.3.7.2 Active Sleep
        3. 7.3.7.3 Passive Sleep
      8. 7.3.8  Mirror Mode
      9. 7.3.9  Speed Optimization
      10. 7.3.10 Cable Diagnostics
        1. 7.3.10.1 TDR
      11. 7.3.11 Fast Link Drop
      12. 7.3.12 Jumbo Frames
    4. 7.4 Device Functional Modes
      1. 7.4.1  Copper Ethernet
        1. 7.4.1.1 1000BASE-T
        2. 7.4.1.2 100BASE-TX
        3. 7.4.1.3 10BASE-Te
      2. 7.4.2  Fiber Ethernet
        1. 7.4.2.1 1000BASE-X
        2. 7.4.2.2 100BASE-FX
      3. 7.4.3  Serial GMII (SGMII)
      4. 7.4.4  Reduced GMII (RGMII)
        1. 7.4.4.1 1000Mbps Mode Operation
        2. 7.4.4.2 1000Mbps Mode Timing
        3. 7.4.4.3 10 and 100Mbps Mode
      5. 7.4.5  Media Independent Interface (MII)
      6. 7.4.6  Bridge Modes
        1. 7.4.6.1 RGMII-to-SGMII Mode
        2. 7.4.6.2 SGMII-to-RGMII Mode
        3.       67
      7. 7.4.7  Media Convertor Mode
      8. 7.4.8  Register Configuration for Operational Modes
        1. 7.4.8.1 RGMII-to-Copper Ethernet Mode
        2. 7.4.8.2 RGMII-to-1000Base-X Mode
        3. 7.4.8.3 RGMII-to-100Base-FX Mode
        4. 7.4.8.4 RGMII-to-SGMII Bridge Mode
        5. 7.4.8.5 1000M Media Convertor Mode
        6. 7.4.8.6 100M Media Convertor Mode
        7. 7.4.8.7 SGMII-to-Copper Ethernet Mode
      9. 7.4.9  Serial Management Interface
        1. 7.4.9.1 Extended Register Space Access
          1. 7.4.9.1.1 Read (No Post Increment) Operation
          2. 7.4.9.1.2 Write (No Post Increment) Operation
      10. 7.4.10 Auto-Negotiation
        1. 7.4.10.1 Speed and Duplex Selection - Priority Resolution
        2. 7.4.10.2 Master and Slave Resolution
        3. 7.4.10.3 Pause and Asymmetrical Pause Resolution
        4. 7.4.10.4 Next Page Support
        5. 7.4.10.5 Parallel Detection
        6. 7.4.10.6 Restart Auto-Negotiation
        7. 7.4.10.7 Enabling Auto-Negotiation Through Software
        8. 7.4.10.8 Auto-Negotiation Complete Time
        9. 7.4.10.9 Auto-MDIX Resolution
    5. 7.5 Programming
      1. 7.5.1 Strap Configuration
        1. 7.5.1.1 Straps for PHY Address
        2. 7.5.1.2 Strap for DP83869HM Functional Mode Selection
        3. 7.5.1.3 LED Default Configuration Based on Device Mode
        4. 7.5.1.4 Straps for RGMII/SGMII to Copper
        5. 7.5.1.5 Straps for RGMII to 1000Base-X
        6. 7.5.1.6 Straps for RGMII to 100Base-FX
        7. 7.5.1.7 Straps for Bridge Mode (SGMII-RGMII)
        8. 7.5.1.8 Straps for 100M Media Convertor
        9. 7.5.1.9 Straps for 1000M Media Convertor
      2. 7.5.2 LED Configuration
      3. 7.5.3 Reset Operation
        1. 7.5.3.1 Hardware Reset
        2. 7.5.3.2 IEEE Software Reset
        3. 7.5.3.3 Global Software Reset
        4. 7.5.3.4 Global Software Restart
    6. 7.6 Register Maps
      1. 7.6.1 DP83869 Registers
  9. 8 Application and Implementation
    1. 8.1 Application Information
    2. 8.2 Typical Applications
      1. 8.2.1 Copper Ethernet Typical Application
        1. 8.2.1.1 Design Requirements
        2. 8.2.1.2 Detailed Design Procedure
          1. 8.2.1.2.1 Clock Input
            1. 8.2.1.2.1.1 Crystal Recommendations
            2. 8.2.1.2.1.2 External Clock Source Recommendation
          2. 8.2.1.2.2 Magnetics Requirements
            1. 8.2.1.2.2.1 Magnetics Connection
        3. 8.2.1.3 Application Curves
      2. 8.2.2 Fiber Ethernet Typical Ethernet
        1. 8.2.2.1 Design Requirements
        2. 8.2.2.2 Detailed Design Procedure
          1. 8.2.2.2.1 Transceiver Connections
        3. 8.2.2.3 Application Curves
    3. 8.3 Power Supply Recommendations
      1. 8.3.1 Two-Supply Configuration
      2. 8.3.2 Three-Supply Configuration
    4. 8.4 Layout
      1. 8.4.1 Layout Guidelines
        1. 8.4.1.1 Signal Traces
          1. 8.4.1.1.1 MAC Interface Layout Guidelines
            1. 8.4.1.1.1.1 SGMII Layout Guidelines
            2. 8.4.1.1.1.2 RGMII Layout Guidelines
          2. 8.4.1.1.2 MDI Layout Guidelines
        2. 8.4.1.2 Return Path
        3. 8.4.1.3 Transformer Layout
        4. 8.4.1.4 Metal Pour
        5. 8.4.1.5 PCB Layer Stacking
      2. 8.4.2 Layout Example
  10. 9 Device and Documentation Support
    1. 9.1 Documentation Support
      1. 9.1.1 Related Documentation
    2. 9.2 Receiving Notification of Documentation Updates
    3. 9.3 Support Resources
    4. 9.4 Trademarks
    5. 9.5 Electrostatic Discharge Caution
    6. 9.6 Glossary
  11. 10Revision History
  12. 11Mechanical, Packaging, and Orderable Information

Package Options

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

8.4.1.1 Signal Traces

PCB traces are lossy and long traces can degrade the signal quality. Traces must be kept short as possible. Unless mentioned otherwise, all signal traces should be 50Ω, single-ended impedance. Differential traces should be 50Ω, single-ended and 100Ω differential. Take care that the impedance is constant throughout. Impedance discontinuities cause reflections leading to EMI and signal integrity problems. Stubs must be avoided on all signal traces, especially the differential signal pairs. See Figure 8-10.

Within the differential pairs, the trace lengths must run parallel to each other and matched in length. Matched lengths minimize delay differences, avoiding an increase in common-mode noise and increased EMI.

Length matching is also important on MAC interface. All Transmit signal trace lengths must match to each other and all Receive signal trace lengths must match to each other. When using 1G transmission speeds, the tolerance for length matching is 50 mils. When using 100/10M, the tolerance for length matching is 100 mils.

Ideally, there should be no crossover or via on the signal paths. Vias present impedance discontinuities and should be minimized. Route an entire trace pair on a single layer if possible.

DP83869HM Avoiding Stubs in a Differential Signal PairFigure 8-10 Avoiding Stubs in a Differential Signal Pair

Signals on different layers should not cross each other without at least one return path plane between them.

Coupling between traces is also an important factor. Unwanted coupling can cause cross talk problems. Differential pairs on the other hand, should have a constant coupling distance between them.

For convenience and efficient layout process, start by routing the critical signals first.