The KSZ9021 is a completely integrated triple-speed (10Base-T/100Base-TX/1000Base-T) Ethernet Physical Layer Transceiver for transmission and reception of data over standard CAT-5 unshielded twisted pair (UTP) cable.
The KSZ9021Gxx provides the industry standard Gigabit Media Independent Interface/Media Independent Interface (GMII/MII) for connection to GMII/MII MACs in Gigabit Ethernet Processors and Switches for data transfer at 1000Mbps or 10/100Mbps speed. The KSZ9021Rxx provides the Reduced Gigabit Media Independent Interface (RGMII).
The KSZ9021 reduces board cost and simplifies board layout by using on-chip termination resistors for the four differential pairs and by integrating a LDO controller to drive a low-cost MOSFET to supply the 1.2V core. The KSZ9021 provides diagnostic features to facilitate system bring-up and debugging in production testing and in product deployment. Parametric NAND tree support enables fault detection between KSZ9021 I/Os and board. Micrel LinkMD® TDR-based cable diagnostics permit the identification of faulty copper cabling. Remote and local loopback functions provide verification of analog and digital data paths.
The KSZ9021RL is available in a 64-pin, lead-free E-LQFP package, and is offered as the KSZ9021RN in the smaller 48-pin QFN package. The KSZ9021GN is available in a 64-pin, lead-free QFN package and the KSZ9021GQ is available in a 128-pin, lead-free PQFP package.