DM9331
100 Mbps Twisted Pair/Fiber Ethernet Media Converter Chip
Preliminary 1
Version: DM9331-DS-P02
September 21, 2001
General Description
The DM9331 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 (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 DM9331 connects to another DM9331 for
the twisted pair to the fiber media converter, or fiber to
fiber repeater.
The DM9331 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 DM9331 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 DM9331 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