Micrel, Inc.
KSZ9021RL/RN
Functional Overview
The KSZ9021RL/RN is a completely integrated triple speed (10Base-T/100Base-TX/1000Base-T) Ethernet Physical Layer
Transceiver solution for transmission and reception of data over a standard CAT-5 unshielded twisted pair (UTP) cable.
Its on-chip proprietary 1000Base-T transceiver and Manchester/MLT-3 signaling-based 10Base-T/100Base-TX
transceivers are all IEEE 802.3 compliant.
The KSZ9021RL/RN 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.
On the copper media interface, the KSZ9021RL/RN can automatically detect and correct for differential pair
misplacements and polarity reversals, and correct propagation delays and re-sync timing between the four differential
pairs, as specified in the IEEE 802.3 standard for 1000Base-T operation.
The KSZ9021RL/RN provides the RGMII interface for a direct and seamless connection to RGMII MACs in Gigabit
Ethernet Processors and Switches for data transfer at 10/100/1000Mbps speed.
The following figure shows a high-level block diagram of the KSZ9021RL/RN.
Figure 1. KSZ9021RL/RN Block Diagram
M9999-101309-1.1
October 2009
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MICREL [ MICREL SEMICONDUCTOR ]
