Datenblatt-pdf.com


CLC012 Schematic ( PDF Datasheet ) - National Semiconductor

Teilenummer CLC012
Beschreibung Adaptive Cable Equalizer for ITU-T G.703 Data Recovery
Hersteller National Semiconductor
Logo National Semiconductor Logo 




Gesamt 18 Seiten
CLC012 Datasheet, Funktion
August 1998
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 pro-
vides 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 inter-
nal adaptive loop time constant with one external capacitor.
Features
n Automatic equalization of coaxial and twisted pair cables
n Loss of Signal detect and output mute
n Output eye monitor
n Single supply operation: +5V or −5.2V
n Single-ended or differential input
n Low cost
Applications
n ITU-T G.703 serial data recovery
n Serial digital data routing and distribution
n Serial digital data equalization and reception
n 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
© 1998 National Semiconductor Corporation DS100145
DS100145-4
www.national.com






CLC012 Datasheet, Funktion
Typical Performance Characteristics (Continued)
DS100145-8
DS100145-13
DS100145-12
DS100145-16
www.national.com
DS100145-14
6
DS100145-39

6 Page









CLC012 pdf, datenblatt
Typical Applications (Continued)
CLC005 driver. Loss of Signal (LOS) is connected to MUTE
to latch outputs DO and DO in the absence of an input signal
to the equalizer.
Refer to the CLC012’s evaluation board layout for additional
suggestions.
National can supply most of the major components required
to design a transmission line repeater. Figure 11 shows a
typical repeater design using the CLC005, CLC012, and the
CLC016. The design functions supported by each chip are:
CLC005: Cable connection chip
Boosts drive for transmission to next repeater or
final destinations
CLC012: Receive serialized digital data from incoming
transmission lines
Equalizes the incoming data
CLC016: Retimes the equalized data (improving jitter)
The CLC016 is a multi-rate data retiming PLL. The circuit
(Figure 11) will work at up to 4 different data rates with no ad-
ditional components or manual tuning.
FIGURE 11. Typical Repeater Design
DS100145-31
DIGITAL VIDEO (SDV) ROUTERS
The CLC012 provides performance that complies with the
ITU-T G.703 standard for serial digital data transmission
over coaxial cable. One common application is in routers,
which provide a switching matrix for connecting source
equipment to destination equipment.
Figure 12 shows a typical configuration for a router, including
equalizers, a crosspoint switch, data retimers, and cable
drivers. The CLC012 is used in its standard configuration in
this application, and automatically equalizes cable lengths
from zero meters to greater than 300 meters at 360 MHz
(see plots in Typical Performance Characteristics sec-
tion). The equalized outputs are connected to the differential
inputs of the crosspoint switch. The CLC016 Data Retimer
receives the data from the crosspoint and performs the clock
and data recovery functions, further reducing jitter. Finally,
the retimed data is driven into the coaxial cable by a CLC005
ITU-T G.703 Cable Driver (with two amplitude-adjustable
outputs).
DS100145-32
FIGURE 12. Data Routing Block Diagram
TWISTED PAIR DRIVER
A low-cost medium for transmitting data is twisted pair. Cat-
egory 5 UTP has an attenuation characteristic similar to
Belden 8281 coaxial cable but scaled in length: 120 meters
of Category 5 UTP is roughly equivalent to 300 meters of
Belden 8281 cable. When properly implemented, the
CLC012 will equalize data rates up to 625 Mbps over Cat-
egory 5 UTP. The maximum data rate depends upon the
cable length. A plot of Maximum Data Rate vs Cable Length
www.national.com
12

12 Page





SeitenGesamt 18 Seiten
PDF Download[ CLC012 Schematic.PDF ]

Link teilen




Besondere Datenblatt

TeilenummerBeschreibungHersteller
CLC011Serial Digital Video DecoderNational Semiconductor
National Semiconductor
CLC011CLC011 Serial Dig Video Decoder (Rev. D)Texas Instruments
Texas Instruments
CLC011ACQSerial Digital Video DecoderNational Semiconductor
National Semiconductor
CLC011BCQSerial Digital Video DecoderNational Semiconductor
National Semiconductor
CLC012Adaptive Cable Equalizer for ITU-T G.703 Data RecoveryNational Semiconductor
National Semiconductor

TeilenummerBeschreibungHersteller
CD40175BC

Hex D-Type Flip-Flop / Quad D-Type Flip-Flop.

Fairchild Semiconductor
Fairchild Semiconductor
KTD1146

EPITAXIAL PLANAR NPN TRANSISTOR.

KEC
KEC


www.Datenblatt-PDF.com       |      2020       |      Kontakt     |      Suche