KSZ9021GN Datasheet, PDF (1/53 Pages) Micrel Semiconductor – Gigabit Ethernet Transceiver with GMII / MII Support

KSZ9021GN
Gigabit Ethernet Transceiver
with GMII / MII Support
General Description
Features
The KSZ9021GN 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 unshielded twisted pair (UTP) cable.
The KSZ9021GN provides the industry standard GMII/MII
(Gigabit Media Independent Interface / Media Independent
Interface) for connection to GMII/MII MACs in Gigabit
Ethernet Processors and Switches for data transfer at
1000 Mbps or 10/100Mbps speed.
The KSZ9021GN 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.
• Single-chip 10/100/1000Mbps IEEE 802.3 compliant
Ethernet Transceiver
• GMII/MII standard compliant interface
• Auto-negotiation to automatically select the highest link
up speed (10/100/100Mbps) and duplex (half/full)
• On-chip termination resistors for the differential pairs
• On-chip LDO controller to support single 3.3V supply
operation – requires only external FET to generate 1.2V
for the core
• Jumbo frame support up to 16KB
• 125MHz Reference Clock Output
• Programmable LED outputs for link, activity and speed
The KSZ9021GN 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
identification of faulty copper cabling. Remote and local
loopback functions provide verification of analog and
digital data paths.
The KSZ9021GN is available in a 64-pin, lead-free QFN
package (See Ordering Information).
• Baseline Wander Correction
• LinkMD^® TDR-based cable diagnostics for identification
of faulty copper cabling
• Parametric NAND Tree support for fault detection
between chip I/Os and board.
• Loopback modes for diagnostics
• Automatic MDI/MDI-X crossover for detection and
correction of pair swap at all speeds of operation
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Functional Diagram
LinkMD is a registered trademark of Micrel, Inc.
Micrel Inc. • 2180 Fortune Drive • San Jose, CA 95131 • USA • tel [phone] • fax + 1 [phone] • http://www.micrel.com
September 2010
M9999-091010-1.1