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KSZ8051RNL Physical Layer Transceiver

Micrel’s physical layer transceiver reduces board cost and simplifies board layout by using on-chip termination resistors

Micrel - KSZ8051RNL Physical Layer Transceiver Micrel, Inc.'s KSZ8051RNL is a single supply 10Base-T/100Base-TX Ethernet physical layer transceiver for transmission and reception of data over a standard CAT-5 unshielded twisted pair (UTP) cable.

The KSZ8051 is a highly integrated and compact solution. It reduces board cost and simplifies board layout by using on-chip termination resistors for the differential pairs and by integrating a low noise regulator to supply the 1.2V core. The KSZ8051RNL offers the reduced media independent interface (RMII) for direct connection with MII/RMII compliant Ethernet MAC processors and switches. A 25MHz crystal is used to generate all required clocks, which includes the 50MHz reference clock output for the KSZ8051RNL.

The KSZ8051RNL provides diagnostic features to facilitate system bring-up and debugging in production testing and product deployment. Parametric NAND tree support enables fault detection between KSZ8051 I/Os and board. Micrel LinkMD® TDR-base cable diagnostics permit identification of faulty copper cabling.

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  • Diagram
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  • HP Auto MDI/MDI-X for reliable detection and correction for straight-through and crossover cables with disable and enable option
  • Auto-negotiation to automatically select the highest link up speed (10/100 Mbps) and duplex (half/full)
  • RMII v1.2 Interface support with 50MHz reference clock output to MAC and option to input 50MHz reference clock
  • LinkMD® TDR based cable diagnostics for identification of faulty copper cabling
  • Parametric NAND Tree support for fault detection between chip I/O's and board
  • Single-chip 10Base-T/100Base-TX IEEE 802.3 compliant Ethernet transceiver
  • Back-to-back mode support for 100Mbps copper repeater or media converterRoHS Compliant
  • MDC/MDIO management interface for PHY register configuration
  • LED outputs for link, activity, and speed status indication
  • On-chip termination resistors for the differential pairs
  • Programmable interrupt output
  • Power down and power saving modes
  • Baseline wander correction


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KSZ8051RNL Diagram

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Digi-Key P/N Micrel P/N Description Datasheet
576-3713-ND KSZ8051RNL TXRX PHY 10/T100 3.3V RMII 32QFN Datasheet