CLP200M_03 Datasheet, PDF (5/21 Pages) STMicroelectronics – OVERVOLTAGE AND OVERCURRENT PROTECTION FOR TELECOM LINE

2.3 Ringing mode
Fig. 4 : Switching by voltage during ringing mode.
Fuse
ILG
TIP
R sense
TIPL
TIPS
1
Overcurrent
detector
1/2 CLP200M
Rp
2
OR
SW3 SW1
Overvoltage
detector
Overvoltage
reference
VLG
(+/- 215 V)
FS
GND
CLP200M
ILG
A1
-215
2
1
+215
VLG
3
In ringing mode (Ring relay in position 2), the only ^{For surges occuring between TIP and RING, the}
protection device involved is the CLP200M.
) _{In normal conditions, the CLP200M operates in re-}
t(s ^{gion 1 of A1 curve, and is idle.}
c _{If an overvoltage occuring between TIP (or RING)}
u _{and GND reaches the internal overvoltage}
d _{refe-rence (+/- 215V), the CLP200M acts and the}
ro ^{line is short-circuited to GND. At this time the oper-}
. _{P ating point moves to region 2 for positive surges}
(region 3 for negative surges). Once the surge cur-
te rent disappears, the device returns to its initial
le ^{state (region 1).}
CLP200M acts in the same way. This means that
the CLP200M ensures a tripolar protection.
When used alone, the CLP200M acts at the inter-
nal overvoltage reference level (+/- 215V). Fur-
thermore, it is possible to adjust this threshold level
to a lower voltage by using :
up to 4 fixed external voltage reference (V_Z1 to
V_Z4) (see fig.5a).
bso ^{Fig. 5a : Method to adjust the reference voltage.}
- ^O _Fuse
) _TIP
Obsolete ^{Product(s FS}
R sense
TIPL
TIPS
Overcurrent
detector
OR
SW3 SW1
SW4 SW2
OR
Overvoltage
detector
Overvoltage
reference
(+/- 215 V)
Overvoltage
detector
Overvoltage
reference
(+/- 215 V)
GND
1
Rp
2
VZ1
VZ2
VZ3
RING
Fuse
Overcurrent
detector
RINGL
R sense
RINGS
VZ4
1
Rp
2
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