CLC012
Adaptive Cable Equalizer for ITU-T G.703 Data Recovery
General Description
National’s CLC012 adaptive cable equalizer is a low-cost
monolithic solution for equalizing data transmitted over cable
(or any media with similar dispersive loss characteristics).
The CLC012 simplifies the task of high-speed data recovery
with a one-chip solution and a minimal number of external
components. The equalizer automatically adapts to equalize
any cable length from zero meters to lengths that attenuate
the signal by 40 dB at 200 MHz. This corresponds to 300
meters of Belden 8281 or 120 meters of Category 5 UTP
(unshielded twisted pair).
The CLC012 provides superior jitter performance: 180pspp
for 270 Mbps data that has passed through 200 meters of
Belden 8281 cable. This exceptional performance provides
wide error margin in digital data links. The equalizer operates
on a single supply with a power consumption of only 290
mW. The small 14-pin SOIC package allows for high-density
placement of components for multi-channel applications
such as routers. The equalizer operates over a wide range of
data rates from less than 50 Mbps to rates in excess of 650
Mbps.
The equalizer is flexible in allowing either single-ended or
differential input drive. Its high common mode rejection provides excellent immunity to interference from noise sources.
On-chip quantized feedback eliminates baseline wander.
Additional features include a Loss of Signal output and an
output mute pin which, when tied together, mute the output
when no signal is present. A buffered eye monitor output is
provided, for viewing the equalized signal prior to the com-
parator. Differential AEC pins allow the user to set the internal adaptive loop time constant with one external capacitor.
Features
n
n
n
n
n
n
Automatic equalization of coaxial and twisted pair cables
Loss of Signal detect and output mute
Output eye monitor
Single supply operation: +5V or −5.2V
Single-ended or differential input
Low cost
Applications
n
n
n
n
ITU-T G.703 serial data recovery
Serial digital data routing and distribution
Serial digital data equalization and reception
Data recovery equalization: ATM, CAD networks,
medical, set top terminals, industrial video networks
Key Specifications
n Low jitter: 180pspp @ 270 Mbps through 200 meters of
Belden 8281 coaxial cable
n High data rates: < 50 Mbps to > 650 Mbps
n Excellent input return loss: 19 dB @ 270 MHz
n Low supply current: 68 mA
n Equalizes up to 300+ meters of Belden 8281 or 120
meters of Cat 5 UTP cable
Typical Application
10014504
© 2003 National Semiconductor Corporation
DS100145
www.national.com
CLC012 Adaptive Cable Equalizer for ITU-T G.703 Data Recovery
November 2003