SLUAAA9A October   2020  – May 2021 DP83TD510E

 

  1.   Trademarks
  2. 1Introduction
  3. 2Terminology
  4. 3Establishing a Link
    1. 3.1 Auto-Negotiation
    2. 3.2 Forcing Host-Client Configuration
      1. 3.2.1 AN_CONTROL (address = 0x7200) [reset = 0x1000]
      2. 3.2.2 PMA_PMD_CTRL (address = 0x1834) [reset = 0x4000]
    3. 3.3 1.0 Vpp vs. 2.4 Vpp Operating Mode
  5. 410Base-T1L Cable Parameters
    1. 4.1 Characteristic Impedance
    2. 4.2 Insertion Loss
    3. 4.3 Return Loss
    4. 4.4 Maximum Delay Link
    5. 4.5 Electromagnetic Classifications
    6. 4.6 Differential to Common Mode Conversion
    7. 4.7 Coupling Attenuation
    8. 4.8 DP83TD510 Cable Reach Performance
  6. 5Revision History

3.1 Auto-Negotiation

The 802.3cg standard requires 10Base-T1L PHYs to support auto-negotiation in low-speed-mode (LSM). In LSM, the PHY sends differential Manchester encoded (DME) pages at 625 Kb/s to advertise its capabilities to its link partner.

In normal operation, the DP83TD510E utilizes 3-level Pulse Amplitude Modulation (PAM3) signal transmitted over a single differential pair at 7.5MBd. The 10Base-T1L standard is unique in that it specifies that a PHY may support an increase transmit and receive capability, boosting the PAM3 amplitude from 1.0 Vpp to 2.4 Vpp. The greater transmit capability helps the PHY overcome attenuation over long cable lengths to extend the maximum reach of the PHY.

The DP83TD510E supports hardware and software configurations to advertise 1.0 Vpp or 2.4 Vpp and 1.0 Vpp capability during auto-negotiation. It also has the capability to adapt the transmit voltage to 2.4 Vpp or 1.0 Vpp as determined during auto-negotiation. DP83TD510E by default advertises 1.0 Vpp only. If both 1.0 Vpp and 2.4 Vpp are advertised and the Link Partner also supports 2.4 Vpp, the DP83TD510E will be configured to 2.4 Vpp. The DP83TD510E offers LED based indication to indicate PHY is operating in 2.4 Vpp or 1.0 Vpp operating mode.

This strap defines the voltage level requested by PHY during Auto Negotiation. It is reflected in register 0x020E[12]. While using Force mode for link-up, the strap controls the output voltage and reflects in register 0x18F6[12].

Table 3-1 Transmit Output Operating Voltage Bootstrap
Pin NameStrap NamePin #DefaultSetting
LED_2Strap728001.0 Vpp
12.4 Vpp
Table 3-2 PMA_CTRL (address = 0x18F6) [reset = 0x0000]
Bit Field Type Reset Description
12 CFG_INCR_TX_LVL R/W 0x0 1 = Enable 2.4 Vpp operating mode
0 = Enable 1.0 Vpp operating mode