July 1999
ML6674
ATM 155Mbps UTP Transceiver
GENERAL DESCRIPTION
The ML6674 is a complete monolithic transceiver for
155Mbps NRZ encoded data transmission over category
5 unshielded twisted pair (UTP) and shielded twisted pair
(STP) cables. The ML6674 is compliant with the ATM
155Mbps Twisted Pair Specification. The ML6674 includes
the baseline restoration function and adaptive
equalization which will accurately compensate for line
losses exceeding 100m of UTP.
The ML6674 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.
An ECL 100K compatible buffer at the output interfaces
directly with ATM physical interface chips.
The ML6674 transmit section accepts ECL 100K
compatible NRZ inputs.
FEATURES
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Complies with ATM Forum 155Mbps twisted pair
specification
Integrated baseline wander correction circuit
Integrated adaptive equalization
Transmitter can be externally turned off
(high impedence) for true quiet line
Operates over 100 meters of STP or category 5 UTP
Twisted Pair Cable
32-pin PLCC and TQFP
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s
s
s
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BLOCK DIAGRAM
LPBK
TXOFF
TVCCA
TVCCD
RTSET1
RTSET
RTSET2
TXIN+
TXIN–
TPOUT+
TPOUT–
SD+
SD–
LINK
STATUS
ADAPTIVE
CONTROL
RXOUT+
MUX
RXOUT–
ADAPTIVE
EQUALIZER
ADAPTIVE
CONTROL REFERENCE
TPIN+
TPIN–
RRSET1
TGNDA TGNDD
RGND
RRSET
RRSET2
RVCCA RVCCD CMREF
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MICRO-LINEAR [ MICRO LINEAR CORPORATION ]
