SNLS654C April   2021  – November 2024 DP83TC812R-Q1 , DP83TC812S-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
  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 Diagnostic Tool Kit
        1. 7.3.1.1 Signal Quality Indicator
        2. 7.3.1.2 Electrostatic Discharge Sensing
        3. 7.3.1.3 Time Domain Reflectometry
        4. 7.3.1.4 Voltage Sensing
        5. 7.3.1.5 BIST and Loopback Modes
          1. 7.3.1.5.1 Data Generator and Checker
          2. 7.3.1.5.2 xMII Loopback
          3. 7.3.1.5.3 PCS Loopback
          4. 7.3.1.5.4 Digital Loopback
          5. 7.3.1.5.5 Analog Loopback
          6. 7.3.1.5.6 Reverse Loopback
      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
    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 Ack
      6. 7.4.6  Sleep Request
      7. 7.4.7  Sleep Fail
      8. 7.4.8  Sleep
      9. 7.4.9  Wake-Up
      10. 7.4.10 TC10 System Example
      11. 7.4.11 Media Dependent Interface
        1. 7.4.11.1 100BASE-T1 Master and 100BASE-T1 Slave Configuration
        2. 7.4.11.2 Auto-Polarity Detection and Correction
        3. 7.4.11.3 Jabber Detection
        4. 7.4.11.4 Interleave Detection
      12. 7.4.12 MAC Interfaces
        1. 7.4.12.1 Media Independent Interface
        2. 7.4.12.2 Reduced Media Independent Interface
        3. 7.4.12.3 Reduced Gigabit Media Independent Interface
        4. 7.4.12.4 Serial Gigabit Media Independent Interface
      13. 7.4.13 Serial Management Interface
        1. 7.4.13.1 Direct Register Access
        2. 7.4.13.2 Extended Register Space Access
        3. 7.4.13.3 Write Operation (No Post Increment)
        4. 7.4.13.4 Read Operation (No Post Increment)
        5. 7.4.13.5 Write Operation (Post Increment)
        6. 7.4.13.6 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 DP83TC812 Registers
  9. 8 Application and Implementation
    1. 8.1 Application Information Disclaimer
    2. 8.2 Application Information
    3. 8.3 Typical Applications
      1. 8.3.1 Design Requirements
        1. 8.3.1.1 Physical Medium Attachment
          1. 8.3.1.1.1 Common-Mode Choke Recommendations
      2. 8.3.2 Detailed Design Procedure
      3. 8.3.3 Application Curves
    4. 8.4 Power Supply Recommendations
    5. 8.5 Layout
      1. 8.5.1 Layout Guidelines
        1. 8.5.1.1 Signal Traces
        2. 8.5.1.2 Return Path
        3. 8.5.1.3 Metal Pour
        4. 8.5.1.4 PCB Layer Stacking
      2. 8.5.2 Layout Example
  10. 9 Device and Documentation Support
    1. 9.1 Receiving Notification of Documentation Updates
    2. 9.2 Support Resources
    3. 9.3 Community Resources
    4. 9.4 Trademarks
    5. 9.5 Electrostatic Discharge Caution
    6. 9.6 Glossary
  11. 10Revision History
  12. 11Mechanical, Packaging, and Orderable Information

7.4.12.3 Reduced Gigabit Media Independent Interface

The DP83TC812-Q1 also supports Reduced Gigabit Media Independent Interface (RGMII) as specified by RGMII version 2.0 with LVCMOS. RGMII is designed to reduce the number of pins required to connect MAC and PHY. To accomplish this goal, the control signals are multiplexed. Both rising and falling edges of the clock are used to sample the control signal pin on transmit and receive paths. Data is samples on just the rising edge of the clock. For 100-Mbps operation, RX_CLK and TX_CLK operate at 25MHz.

The RGMII signals are summarized in Table 7-11:

Table 7-11 RGMII Signals
FUNCTIONPINS
Data SignalsTX_D[3:0]
RX_D[3:0]
Control SignalsTX_CTRL
RX_CTRL
Clock SignalsTX_CLK
RX_CLK
DP83TC812S-Q1 DP83TC812R-Q1 RGMII ConnectionsFigure 7-16 RGMII Connections
Table 7-12 RGMII Transmit Encoding
TX_CTRL
(POSITIVE EDGE)		TX_CTRL
(NEGATIVE EDGE)		TX_D[3:0]DESCRIPTION
000000 through 1111Normal Inter-Frame
010000 through 1111Reserved
110000 through 1111Normal Data Transmission
100000 through 1111Transmit Error Propagation
Table 7-13 RGMII Receive Encoding
RX_CTRL
(POSITIVE EDGE)		RX_CTRL
(NEGATIVE EDGE)		RX_D[3:0]DESCRIPTION
000000 through 1111Normal Inter-Frame
010000 through 1101Reserved
011110False Carrier Indication
011111Reserved
100000 through 1111Normal Data Reception
110000 through 1111Data Reception with Errors

During packet reception, RX_CLK may be stretched on either the positive or negative pulse to accommodate the transition from the internal free running clock to a recovered clock (data synchronous). Data may be duplicated on the falling edge of the clock because double data rate (DDR) is only required for 1-Gbps operation, which is not supported by the DP83TC812-Q1.

The DP83TC812-Q1 supports in-band status indication to help simplify link status detection. Inter-frame signals on RX_D[3:0] pins as specified in Table 7-14.

Table 7-14 RGMII In-Band Status
RX_CTRLRX_D3RX_D[2:1]RX_D0
00

Note:

In-band status is only valid when RX_CTRL is low		Duplex Status:

0 = Half-Duplex

1 = Full-Duplex

RX_CLK Clock Speed:

00 = 2.5MHz

01 = 25MHz

10 = 125MHz

11 = Reserved

Link Status:

0 = Link not established

1 = Valid link established