3.4.1.2 Gigabit Ethernet Interface
The KSZ9131RNX is a completely integrated triple-speed (10BASE-T/100BASE-TX/1000BASE-T) Ethernet physical layer transceiver for transmission and reception of data on standard CAT-5 as well as CAT-5e and CAT-6 unshielded twisted pair (UTP) cables.
The KSZ9131RNX provides the Reduced Gigabit Media Independent Interface (RGMII) for direct connection to RGMII MACs in Gigabit Ethernet processors and switches for data transfers at 10/100/1000 Mbps.
The KSZ9131RNX reduces board cost and simplifies board layout by using on-chip termination resistors for the four differential pairs and by integrating an LDO controller to drive a low-cost MOSFET to supply the 1.2V core.
The KSZ9131RNX offers diagnostic features to facilitate system bring-up and debugging in production testing and in product deployment.
An individual unique 48-bit MAC address (Ethernet hardware address) is allocated to this product and is stored in one of the Microchip 24AA025E48 TWI serial EEPROMs described in Dual Serial EEPROM.
Additionally, for monitoring and control purposes, the RJ45 connectors feature a LED functionality to indicate activity, link, and speed status.
| PIO | Signal Name | Shared With | Signal Description |
|---|---|---|---|
| PA15 | ETH0_TXEN_PA15 | – | Transmit enable |
| PA16 | ETH0_TX0_PA16 | – | Transmit data line 0 |
| PA17 | ETH0_TX1_PA17 | – | Transmit data line 1 |
| PA18 | ETH0_RXCTL_PA18 | – | Receive data valid or carrier sense and data valid |
| PA19 | ETH0_RX0_PA19 | – | Receive data line 0 |
| PA20 | ETH0_RX1_PA20 | – | Receive data line 1 |
| PA22 | ETH0_MDC_PA22 | – | Management data clock |
| PA23 | ETH0_MDIO_PA23 | – | Management data input/output |
| PA24 | ETH0_TXCK_PA24 | – | Transmit clock or 50 MHz reference clock |
| PA25 | ETH0_125CK_PA25 | – | 125 MHz clock |
| PA26 | ETH0_TX2_PA26 | – | Transmit data line 2 |
| PA27 | ETH0_TX3_PA27 | – | Transmit data line 3 |
| PA28 | ETH0_RX2_PA28 | – | Receive data line 2 |
| PA29 | ETH0_RX3_PA29 | – | Receive data line 3 |
| PA30 | ETH0_RXCK_PA30 | – | Receive clock |
| PA31 | ETH0_INT_PA31 | – | Ethernet 0 interrupt |
| Pin No. | Signal Name | Signal Description |
|---|---|---|
| 0 | – | Earth ground |
| 1 | – | Digital ground |
| 2 | ETH0_TXRX_D_N | Media Dependent Interface[3], negative signal of differential pair |
| 3 | ETH0_TXRX_D_P | Media Dependent Interface[3], positive signal of differential pair |
| 4 | ETH0_TXRX_C_N | Media Dependent Interface[2], negative signal of differential pair |
| 5 | ETH0_TXRX_C_P | Media Dependent Interface[2], positive signal of differential pair |
| 6 | ETH0_TXRX_B_N | Media Dependent Interface[1], negative signal of differential pair |
| 7 | ETH0_TXRX_B_P | Media Dependent Interface[1], positive signal of differential pair |
| 8 | ETH0_TXRX_A_N | Media Dependent Interface[0], negative signal of differential pair |
| 9 | ETH0_TXRX_A_P | Media Dependent Interface[0], positive signal of differential pair |
| 10 | – | – |
| 11 | – | Green LED anode |
| 12 | – | Green LED cathode |
| 13 | – | Yellow LED anode |
| 14 | – | Yellow LED cathode |