CLP200M_03 Datasheet, PDF (7/21 Pages) STMicroelectronics – OVERVOLTAGE AND OVERCURRENT PROTECTION FOR TELECOM LINE

CLP200M
Fig. 7a and 7b : Switching-on current versus
R_SENSE.
ISWON (mA)
500
300
-20°C 25°C 75°C
200
2.5 . Failure Status
The CLP200M has an internal feature that allows
the user to get a Failure Status (FS) indication.
When the CLP200M is short-circuiting the line to
GND, a signal can be managed through pin 1. This
signal can be used to turn a LED on in order to pro-
vide a surge indication. It may also be used with a
logic circuitry to count the number of disturbances
appearing on the lines.
Fig. 8 : Failure Status circuit and diagnostic.
100
3
5
7
Rsense (Ω)
9 11 13
Rsense
1
Iswon @ 25°C (mA)
FAILURE
CLP200M
500
t(s) ³⁰⁰
uc 200
Iswon min
negative
Iswon max
negative
Iswon min
positive
Iswon min
positive
STATUS
1k
+12V
Rsense
Prod 100
lete ³
5
7
Rsense (Ω)
9 11
bso _{The choice of the switching-on current is function}
O _{of the RSENSE resistors.}
) ^{- In normal operating condition, only the negative}
t(s ^{current of the signal is of interest. This current (typ-}
ically below -150 mA) should not activate the pro-
c _{tection device CLP200M. Therefore the level of}
u _{activation is to be chosen just above this limit (typi-}
d _{cally -200 mA). This level is adjusted through}
ro RSENSE.
P _{Figures 7a and 7b enable the designers to choose}
te ^{the right RSENSE value.}
sole _{EXAMPLE :}
Ob^{The choice of RSENSE = 4 Ω ensures a negative}
If a surge exceeding the maximum ratings of the
CLP200M occurs on the line, the device will fail in a
short-circuit state.
Fig. 9 : Operation limits and destruction zone of
the CLP200M.
Ipp (A)
1000
100
10
0.01
0.1
1
10
t (ms)
The figure 9 shows two different curves :
s The lower one indicates the maximum
triggering of -220 mA min and -320 mA max. In this
guaranted working limits of the CLP200M.
case, the positive triggering will be 180mA min and
280 mA max.
s The upper curve shows the limit above which the
CLP200M is completely destructed . In this case,
the Fail Diagnostic pin is on.
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