PRELIMINARY
This document contains information on a product under development at Advanced Micro Devices. The information
is intended to help you evaluate this product. AMD reserves the right to change or discontinue work on this proposed
product without notice.
Publication# 22164 Rev: AAmendment/+2
Issue Date: February 1999
Refer to AMD’s Website (www.amd.com) for the latest information.
Am79C873
NetPHY™ -1
10/100 Mbps Ethernet Physical Layer Single-Chip Transceiver with 100BASE-FX Support
DISTINCTIVE CHARACTERISTICS
■
100BASE-FX direct interface to industry
standard electrical/optical transceivers
■
10/100BASE-TX physical-layer, single-chip
transceiver
■
Compliant with the IEEE 802.3u 100BASE-TX
standard
■
Compliant with the ANSI X3T12 TP-PMD 1995
standard
■
Compliant with the IEEE 802.3u Auto-
Negotiation protocol for automatic link type
selection
■
Supports the MII with serial management
interface
■
Supports Full Duplex operation for 10 Mbps and
100 Mbps
■
High performance 100 Mbps clock generator
and data recovery circuitry
■
Adaptive equalization circuitry for 100 Mbps
receiver
■
Controlled output edge rates in 100 Mbps
■
Supports a 10BASE-T interface without the
need for an external filter
■
Provides Loopback mode for system
diagnostics
■
Includes flexible LED configuration capability
■
Digital clock recovery circuit using advanced
digital algorithm to reduce jitter
■
Low-power, high-performance CMOS process
■
Available in a 100-pin PQFP package
GENERAL DESCRIPTION
The NetPHY-1 device is a physical-layer, single-chip,
low-power transceiver for 100BASE-TX, 100BASE-FX,
and 10BASE-T operations. On the media side, it pro-
vides a direct interface to Fiber Media for 100BASE-FX
Fast Ethernet, Unshielded Twisted Pair Category 5
Cable (UTP5) for 100BASE-TX Fast Ethernet, or
UTP5/UTP3 Cable for 10BASE-T Ethernet. Through
the IEEE 802.3u Media Independent Interface (MII),
the NetPHY-1 device connects to the Medium Access
Control (MAC) layer, ensuring a high interoperability
among products from different vendors.
The NetPHY-1 device uses a low-power, high-perfor-
mance CMOS process. It contains the entire physical
layer functions of 100BASE-FX and 100BASE-TX as
defined by the IEEE 802.3u standard, including the
Physical Coding Sublayer (PCS), Physical Medium
Attachment (PMA), 100BASE-TX Twisted Pair Physical
Medium Dependent (TP-PMD) sublayer, and a
10BASE-T Encoder/Decoder (ENDEC). The NetPHY-1
device provides strong support for the Auto-Negotiation
function utilizing automatic media speed and protocol
selection. The NetPHY-1 device incorporates an inter-
nal wave-shaping filter to control rise/fall time, eliminat-
ing the need for external filtering on the 10/100
Mbps signals.
