Typical SLIC Protection Concept.

APPLICATION CIRCUIT

RING

RELAY

RING GENERATOR

PTC

PTC

LINE A

LINE B

THBT200S

LCP150S

-V

BAT

SLIC

T

E

S

T

R

E

L

A

Y

220

nF

S

FUNCTIONAL DESCRIPTION

LINE A PROTECTION:

- For positive surges versus GND, the diode D1

will conduct.

- For negative surges versus GND, the protec-

tion device P1 will trigger at a voltage fixed by

the -VBAT reference.

LINE B PROTECTION:

- For surges on Line B, the operating mode is the

same , D2 or P2 is activated.

A capacitor (C = 220nF) can be added close to

the gate of the LCP15xx, in order to speed up

the triggering.

®

LCP150S

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