AN1220 Datasheet, PDF (1/13 Pages) STMicroelectronics – LINECARD PROTECTION BY OVERVOLTAGE AND OVERCURRENT WITH A CLP270M

®
A.S.Dä
AN1220
APPLICATION NOTE
LINECARD PROTECTION BY OVERVOLTAGE
AND OVERCURRENT WITH A CLP270M
P.Merceron / A.Bremond
INTRODUCTION
This device includes a primary protection level and is suitable for main distribution frames and line cards.
This protection concept is explained and, in addition, the CLP270M performances are analysed when
facing different surges as described in the BELLCORE GR 1089 recommendations.
Figure 1 is a simplified block diagram of a subscriber line protection that is commonly used.
Fig. 1: Subscriber line protection topology
uct(s) ^{Telecommunication}
rod ^line
“PRIMARY PROTECTION”
CLP270M
MDF
“SECONDARY PROTECTION”
SLIC
LINE CARD
te ^{P EXCHANGE}
bsole _{Telecommunication}
ct(s) ^{- O line}
MDF
“SECONDARY PROTECTION”
CLP270M
THDTxx
or
LCP1511D
or
LCDP1511D
SLIC
LINE CARD
EXCHANGE
rodu ^{This shows two different topologies :}
P ^{n A “primary protection” located on the Main Distribution Frame (MDF) eliminates coarsely the high energy}
environmental disturbances (lightning transients and AC power mains disturbances)
te _{n A “secondary protection” located on the line card includes a primary protection level (first stage) and a}
le residual protection (second stage) which eliminates finely the remaining transients that have not been totally
Obso ^{suppressed by the first stage.}
January 2000
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