GENERAL DESCRIPTION

The ML6673 is a complete monolithic transceiver for 125 Mbaud MLT-3 encoded data transmission over Category 5 unshielded twisted pair and shielded twisted pair cables. The ML6673 integrates the baseline restoration function defined in the TP-PMD standard. The adaptive equalizer in the ML6673 will accurately compensate for line losses exceeding the IEEE 802.3u limit of 100m of UTP.

The ML6673 receive section consists of an equalizing filter with a feedback loop for controlling effective line compensation. The feedback loop contains a filter and detection block for determining the proper control signal. The ML6673 also contains data comparators with precisely controlled slicing thresholds and an MLT-3 to NRZI translator.

The ML6673 transmit section accepts ECL 100K compatible NRZ inputs and converts them to differential current mode MLT-3 signals. Transmit amplitude is controlled by a single external resistor.

FEATURES

■ Compliant with IEEE 802.3u Fast Ethernet (100BASE-TX) standard

■ Compliant with ANSI X3T12 FDDI over copper (TP-PMD) standard

■ Integrated baseline wander correction circuit

■ Transmitter converts NRZI ECL signals to MLT-3 current driven outputs

■ Transmitter can be externally turned off (high impedence) for true quiet line

■ Receiver includes adaptive equalizer and MLT-3 to NRZI decoder

■ Operates over 100 meters of STP or category 5 UTP Twisted Pair Cable set by the IEEE 802.3u standards

■ 32-pin PLCC and TQFP