DM9331AE Product Brief

100 Mbps Twisted Pair/Fiber Ethernet Media Converter Chip

June 2008 Rev.1.0

The DM9331A is a physical-layer, single-chip, low power transceiver for media

converter application. On the media side, it provides a direct interface either to

Unshielded Twisted Pair Category 5 Cable 5 (UTP5) for 100BASE-TX Fast Ethernet,

and it also provides PECL interface to connect the external fiber optical transceiver.

Through the Media Converter Interface (MCI), the DM9331A connects to another

DM9331A for the twisted pair to the fiber media converter, or fiber to fiber repeater.

The DM9331A uses a low-power and high-performance CMOS process. It contains

the entire physical layer functions of 100BASE-TX as defined by IEEE802.3u,

including the Physical Coding Sublayer (PCS), Physical Medium Attachment (PMA),

Twisted Pair Physical Medium Dependent Sublayer (TP-PMD) and a PECL compliant

interface for a fiber optical module, compliant with ANSI X3.166. The DM9331A

provides a strong support for the auto-negotiation function, utilizing automatic

selection of full or half-duplex mode. Furthermore, due to the built-in wave-shaping

filter, the DM9331A needs no external filter to transport signals to the media on the

100base-TX Ethernet operation.

Block Diagram

MII

Management

Control

Biasing/

Power

Block

Clock

Circuit

Block

100Base-TX

Transceiver

100Base-FX

PECL

Interface

LED Driver

Media

Converter

Interface

MII

Register

100Base-

TX

PCS

Auto-Negotiation

TX/RX Module