
DM9301
100Mbps Ethernet Fiber/Twisted Pair Single Chip Media Converter
Final 1
Version: DM9301-DS-F02
May 8, 2000
General Description
The DM9301 is a physical-layer, single-chip, low-
power media converter for 100BASE-TX/FX full
duplex repeater applications. On the TX media side,
it provides a direct interface to Unshielded Twisted
Pair Cable 5 (UTP5) for 100BASE-TX Fast Ethernet.
On the FX media side, it provides a direct interface to
a Pseudo Emitter Coupled Logic level interface
(PECL).
The DM9301 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 optic module, compliant with ANSI X3.166.
The DM9301 provides two independent clock
Block Diagram
recovery circuits to minimize bit delay through the
converter (no FIFO are used to buffer data between
the FX and TX interfaces). Furthermore, due to the
excellent rise/fall time control by a built-in wave-
shaping filter, the DM9301 needs no external filter to
transport signals to the media on the 100Base-TX
interface.
Patent-Pending Circuits
Smart adaptive receiver equalizer
Digital algorithm for high frequency clock/data
recovery circuit
High speed wave-shaping circuit
TX Code-
group
Alignment
Monitor
Descrambler
Serial to
Parallel
NRZI
to
NRZ
RX
CRM
MLT-3 to
NRZI
Adaptive
EQ
CGM
125M TPRXCLK
25M TPRXCLK
25M
OSC/XTAL
TPRXI+/-
Parallel
to Serial
FX Code-
group
Alignment
Monitor
Serial to
Parallel
RX
CRM
Scrambler
Parallel
to Serial
NRZ
to
NRZI
NRZI to
MLT-3
MLT-3
Driver
TPTXO+/-
Rise/Fall
Time
CTL
25M FXRXCLK
125M FXRXCLK
PECL
TXMT
PECL
RCVR
PECLRXI +/-
PECLTXO +/-
FXSD
RCVR
Link Status
Monitor &
LED Driver
PECLSD
NRZ
to
NRZI
NRZI
to
NRZ